Automotive News, Media & Press - Ward's 10 Best Engines for 2009

Ward's Auto has released its annual list of Ten Best Engines for the new year, and our first assessment is that it's just as interesting for what isn't present as for what is. First of all, let's get the official list out of the way:

* Audi AG: 2.0L TFSI turbocharged DOHC I-4 (A4 Avant)
* BMW AG: 3.0L turbocharged DOHC I-6 (135i Coupe)
* BMW AG: 3.0L DOHC I-6 Turbodiesel (335d)
* Chrysler LLC: 5.7L Hemi OHV V-8 (Dodge Ram/Challenger R/T)
* Ford Motor Co.: 2.5L DOHC I-4 HEV (Escape Hybrid)
* General Motors Corp.: 3.6L DOHC V-6 (Cadillac CTS)
* Honda Motor Co. Ltd.: 3.5L SOHC V-6 (Accord Coupe)
* Hyundai Motor Co. Ltd.: 4.6L DOHC V-8 (Genesis)
* Toyota Motor Corp.: 3.5L DOHC V-6 (Lexus IS 350)
* Volkswagen AG: 2.0L SOHC I-4 Turbodiesel (Jetta TDI)

Take a good look. Nissan's ubiquitous VQ, which up to this point, was the only engine series that had made Ward's Ten Best ever since the list's inception in 1995, is conspicuously absent. That's a big deal. We also note a couple of turbodiesel engines, one in BMW's favored inline-six configuration and one that powers VW's Jetta TDI. Ford's updated 2.5L hybrid four cylinder is also recognized, rounding out this year's trio of green powerplants. We also note that there's only one American V8 engine, the redesigned HEMI from Chrysler. More snubs? How'd they miss the amazing powerplants that sit under the hoods of the Corvette ZR1 and the Nissan GT-R? Update: Thanks goes to our commentators, who point out that the ZR1 and GT-R are too expensive to make the list.
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Does anyone know the criteria that Ward uses to determine which engines make the 10 best list?

Probably not cost of repair and long term dependability.

Probably not cost of repair and long term dependability.

No kidding. It's amazing how people think its a given that writers are experts on the topic they’re writing about.

Well the two plants from BMW are proven and dependable. Glad to see they have 2 on the list.

A lot of people still disagree with the fact that GM is still using pushrods. And while they make great power and are dependable, they aren't groundbreaking. On top of that, they don't break new ground in gas mileage either. It's the simple fact that with an M6 trans, you CAN get decent mileage if you cruising the highway in 6th.

Direct Injection, variable cam timing, DOHC design, etc. are all absent in the design. So from a technological standpoint, it's pretty obvious why an LSX isn't on there.

Well the two plants from BMW are proven and dependable. Glad to see they have 2 on the list.

A lot of people still disagree with the fact that GM is still using pushrods. And while they make great power and are dependable, they aren't groundbreaking. On top of that, they don't break new ground in gas mileage either. It's the simple fact that with an M6 trans, you CAN get decent mileage if you cruising the highway in 6th.

Direct Injection, variable cam timing, DOHC design, etc. are all absent in the design. So from a technological standpoint, it's pretty obvious why an LSX isn't on there.


If you look at some of the poor gas mileage numbers on the Toyota FJ and 4runner and others you can easily argue against putting a DOHC engine in a truck vs a OHV design such as the LS. Average fuel economy on a V8 4runner is 14mpg and that with DOHCs and VVT.

Additionally, the argument against the pushrod motor for being a dinosour is kind of moot considering that the ohc motor is nearly as old~1919.

I'm not saying the LS motors should be on the list, but I would not rule out a motor because it is a OHV design. VVT, direct injection and DOD can be applied to both style engines.

If you look at some of the poor gas mileage numbers on the Toyota FJ and 4runner and others you can easily argue against putting a DOHC engine in a truck vs a OHV design such as the LS. Average fuel economy on a V8 4runner is 14mpg and that with DOHCs and VVT.

Additionally, the argument against the pushrod motor for being a dinosour is kind of moot considering that the ohc motor is nearly as old~1919.

I'm not saying the LS motors should be on the list, but I would not rule out a motor because it is a OHV design. VVT, direct injection and DOD can be applied to both style engines.

I find that kind of funny, also. If something works then use it.
People just rag on push rods because it is a proven design and they think the latest trend is better. Not always...

I have also found out that a lot of people think continuous variable transmissions are new but their are actually designs out there more than 100 years old!

Many of the first automobiles were electric. Not as many people think. So technically, the electric car is old news.

I agree that the Toyota V8 gets some of the worst mileage in the class.

I'm not saying I agree with the argument either, just that people still use it as a negative point.

But from personal experience, (I'm a BMW Tech) the N54 motor is phenomenal. Especially since the bugs have been worked out since its debut. Cost of maintenance, and dependability aren't really a factor. But with anything, cost is all relative.

Ever wonder what the 10 Worst Engines for 2009 should be?

Well I hate to break it to you guys, but the Ward's people aren't biased against pushrods....

The Buick 3800 was on the list for almost two decades IIRC. The magazines might have called it thrashy but it kept showing up on the list and people kept buying the engines....

Also, that TFSI engine from Audi is a fantastic powerplant...now if only they would put it into a Mid engine platform car instead of all these stupid torque-steering VW's and A4's....Trust me, I drove the GLI. Fantastic engine....zero grip.

The GM 3.6 V6 is a damn good engine. I have one in my daily driver. Makes decent power and with the A6 gets almost 29 mpg.

ls3 > 5.7 hemi
ecotec 2.0 DI turbo > audi 2.0T


Sad to say it... But i would like to see GM produce a dohc small displacement v8 to compete with the Genesis 4.6 v8 and Ford Mod na motors. Keep the LSX engine architecture and update to a gen 5 ohv LSX.

I would like to see these motors in the future.

Gen 5 LSX
LSB = 376ci DI with e85
LSC = 408ci DI SC with e85
LSD = 500+ci DI VVT with e85

DOHC V8 / XV8
4.0 DI AFM E85
4.8 DI VVT E85
5.0 DI Turbo E85

ls3 > 5.7 hemi
ecotec 2.0 DI turbo > audi 2.0T


Sad to say it... But i would like to see GM produce a dohc small displacement v8 to compete with the Genesis 4.6 v8 and Ford Mod na motors. Keep the LSX engine architecture and update to a gen 5 ohv LSX.

I would like to see these motors in the future.

Gen 5 LSX
LSB = 376ci DI with e85
LSC = 408ci DI SC with e85
LSD = 500+ci DI VVT with e85

DOHC V8 / XV8
4.0 DI AFM E85
4.8 DI VVT E85
5.0 DI Turbo E85


But an LS3 doesn't need DOHCs to compete, besides the DOHC motors take up too much room in the engine compartment. DOD yes, Direct injection yes, DOHCs and their extra complexity not needed.

ls3 > 5.7 hemi
ecotec 2.0 DI turbo > audi 2.0T


Sad to say it... But i would like to see GM produce a dohc small displacement v8 to compete with the Genesis 4.6 v8 and Ford Mod na motors. Keep the LSX engine architecture and update to a gen 5 ohv LSX.

I would like to see these motors in the future.

Gen 5 LSX
LSB = 376ci DI with e85
LSC = 408ci DI SC with e85
LSD = 500+ci DI VVT with e85

DOHC V8 / XV8
4.0 DI AFM E85
4.8 DI VVT E85
5.0 DI Turbo E85



I'd love to see that too :jest:

But an LS3 doesn't need DOHCs to compete, besides the DOHC motors take up too much room in the engine compartment. DOD yes, Direct injection yes, DOHCs and their extra complexity not needed.

No the LS3 doesnt need dohc of course. Google GM's XV8, that would be a killer engine to compete with the jap and euro v8s.

I'd love to see that too :jest:
Driving a vette with a high compression 500ci lsx would be like tripping on LSD :chug:.

if you look a couple years back with the Wards 10 best engines the LS1 does get in the 99' and 98'

http://en.wikipedia.org/wiki/Ward%27s_10_Best_Engines

ls3 > 5.7 hemi
ecotec 2.0 DI turbo > audi 2.0T


Sad to say it... But i would like to see GM produce a dohc small displacement v8 to compete with the Genesis 4.6 v8 and Ford Mod na motors. Keep the LSX engine architecture and update to a gen 5 ohv LSX.

I would like to see these motors in the future.

Gen 5 LSX
LSB = 376ci DI with e85
LSC = 408ci DI SC with e85
LSD = 500+ci DI VVT with e85

DOHC V8 / XV8
4.0 DI AFM E85
4.8 DI VVT E85
5.0 DI Turbo E85

How soon we forget the NorthStar.... It''s being used in Supercharged form in the STS-V and XLR-V and in N/A form in the same cars as well as the DTS. GM HAS had a small displacement (relatively) DOHC V8 for LONG time...

The Northstar engines are a joke competitively. They are very outdated.

The Northstar engines are a joke competitively. They are very outdated.Well, I don't know if I'd go that far...they may not be exactly cutting edge anymore but they're FAR from outdated or obsolete.

What exactly would you say makes the northstar outdated? Odd especially from someone that has lt1 power in their sig. Not trying to dog, but the engines actually have quite the potential, example the sts-v powerplant. You could buy the crate engine blown making 460hp. Compare that to lets say an 03/04 cobra powerplant. The northstar is smaller, but makes more power. I'm sure there are a few other details that could affect that (supercharger size, boost, etc) but in the muscle car world the mod engine seems to be the ohv contender, but the northstar is definitely not out of that league as far as power goes. We all know neither are as fuel efficient as the lsx engines. Please correct me if I'm wrong on any of this.

The list itself makes sense, especially with BMW being on there. The only engine that really stumps me is the new Hemi. Granted, I'm not very well informed in the modern mopar world, but I feel like maybe theres something I'm missing if it made that list...

The LSx engines aren't themselves really all that fuel-efficient... it's the low transmission gearing that makes them so. A .5:1 6th gear (double overdrive) makes a world of an impact. Great engines, but it's the whole drivetrain that makes them so fuel efficient, not the engine itself.

I understand that, I used to have a 99 silverado with a 5.3L and 4:10s. Wasn't exactly a green vehicle. Still when I kept the throttle under control it did pretty well.

I'm really wondering what makes the new hemi's better as an engine overall than any current ls based engine. Also wish they had a separate list without a price cap on it, I'd like to see their opinions on the ls9, along with bugattis w16. Those freaks at bugatti are picasso's of engine design.

The LSx engines aren't themselves really all that fuel-efficient... it's the low transmission gearing that makes them so. A .5:1 6th gear (double overdrive) makes a world of an impact. Great engines, but it's the whole drivetrain that makes them so fuel efficient, not the engine itself.Good point and basically true, but even in vehicles (F-bodies, GTOs, earlier trucks) equipped with only four gears (and only one overdrive) the fuel efficiency of the LSx family of engines was/is still pretty damn good.
I got over 26+mpg in my automatic Z28 (and that's with 3.23 gears, not the even more fuel efficient 2.73s) on a long trip to St. Louis and back at times averaging up to 75-80mph.
But yes, the 6 speed manuals and, more recently, the 6 speed automatics play a role in the awesome fuel economy numbers delivered by the LSx. :nod:

The only engine that really stumps me is the new Hemi. Granted, I'm not very well informed in the modern mopar world, but I feel like maybe theres something I'm missing if it made that list...I'm really wondering what makes the new hemi's better as an engine overall than any current ls based engine.I agree with you, if the Hemi makes it onto the list than so should the LS3. :nod:
And if you look closely at the design of the current Chrysler Hemis you will see many similarities between it and the LSx series of motors, they borrowed a lot from the original LS1 design. :cool:

The LNF should be on that list for like 5 straight years.

I understand that, I used to have a 99 silverado with a 5.3L and 4:10s. Wasn't exactly a green vehicle. Still when I kept the throttle under control it did pretty well.

I'm really wondering what makes the new hemi's better as an engine overall than any current ls based engine. Also wish they had a separate list without a price cap on it, I'd like to see their opinions on the ls9, along with bugattis w16. Those freaks at bugatti are picasso's of engine design.

The problem with the LS7 and LS9 (in terms of this list) is that they themselves don't really break any ground... they're just additions to the LS1. The LS7 isn't really anymore efficient than the LS1 in terms of power/size, so why would they put them on the list for just making it bigger? And the GT500 Super Snake has more of a chance to make it than the LS9. But in reality, neither will make it.

And the GT500 Super Snake has more of a chance to make it than the LS9. But in reality, neither will make it.

That I highly disagree with. LS9 has many new features no ls engine has seen before aside from race cars, such as oil squirters. Super Snake is just a bigger engine with a bigger blower and a raised price tag. The thing about the ls9 is the fact it has a compact new cooling unit, low blower profile, as well of the fact that it is supposed to be very tame and more streetable to drive than an ls7.

Not saying the Super Snakes engine isn't good, but what makes it superior in design to previous modulars?

Oil squirters are nothing revolutionary... Integra GS-Rs had them back in 1994. And the blower is an Eaton unit, not Chevrolet. The 5.4 in the Super Snake has internals that have been proven to handle well over 1,000rwhp, and doesn't require any head/cam changes to do so, which is quite impressive. But both engines are just adaptations to existing motors, using some basically aftermarket parts. Which is why neither are gonna make the list.

They've really picked some winners from years past


2003 Ford Powerstroke- total pos motor
2004 Mazda wankel rotory- recalled due to them blowing up/using oil
2000 Jag AJ V8-Nikasil cylinder liners caused motors to blow up
1997 Caddy Northstar- blows headgaskets

The LS7 isn't really anymore efficient than the LS1 in terms of power/size, so why would they put them on the list for just making it bigger?
Because its a 440lbs engine(dressed) that makes 505 restricted hp and 470 restricted ft.lbs of torque, and is no bigger than the LS1 (and smaller still than even many V6's on the market).
The problem with the "Ward's best engines" is they select their engines based on irrelevant numbers on paper (like hp/l) instead of real world figures that are actually meaningful (like weight and physical size). I don't think its at all a coincidence that we see so many supercars and kit cars that are using LSx based engines opposed to some more exotic engines out there. Why do you think that is?

Wards isn't too different from any other magazine. I don't know why anyone gets their shorts in bind over any friggen magazine list. When I sold Nissans I used the fact about their V6. The Mazda Rotary also made Wards list.

Now that I have this information I see it as an excuse to drink another beer tonight, thanks!!

Jakes Dad

Because its a 440lbs engine(dressed) that makes 505 restricted hp and 470 restricted ft.lbs of torque, and is no bigger than the LS1 (and smaller still than even many V6's on the market).
The problem with the "Ward's best engines" is they select their engines based on irrelevant numbers on paper (like hp/l) instead of real world figures that are actually meaningful (like weight and physical size). I don't think its at all a coincidence that we see so many supercars and kit cars that are using LSx based engines opposed to some more exotic engines out there. Why do you think that is?

And you make it sound like I didn't just defend the LSx motors. They are great engines, and have already been honored in '98 and '99 I believe. But honestly the LS9 is an LS3... with a blower. Just like the LS7 is, for all intents and purposes, a bored/stroked LS2. Again, very good motors, just don't fit the criteria. Like the sub-$54,000 entry fee. Not many people are gonna see the benefit of a $70k+ car.

And you make it sound like I didn't just defend the LSx motors. They are great engines, and have already been honored in '98 and '99 I believe. But honestly the LS9 is an LS3... with a blower. Just like the LS7 is, for all intents and purposes, a bored/stroked LS2. Again, very good motors, just don't fit the criteria. Like the sub-$54,000 entry fee. Not many people are gonna see the benefit of a $70k+ car.

I will end here. In regard to the fact you seem to respect the lsx platform, as I the modular, and both with opinions that don't change the topic at hand.

What exactly would you say makes the northstar outdated? Odd especially from someone that has lt1 power in their sig. Not trying to dog, but the engines actually have quite the potential, example the sts-v powerplant. You could buy the crate engine blown making 460hp. Compare that to lets say an 03/04 cobra powerplant. The northstar is smaller, but makes more power. I'm sure there are a few other details that could affect that (supercharger size, boost, etc) but in the muscle car world the mod engine seems to be the ohv contender, but the northstar is definitely not out of that league as far as power goes. We all know neither are as fuel efficient as the lsx engines. Please correct me if I'm wrong on any of this.

The list itself makes sense, especially with BMW being on there. The only engine that really stumps me is the new Hemi. Granted, I'm not very well informed in the modern mopar world, but I feel like maybe theres something I'm missing if it made that list...

LOL at the LT1 bashing..... Some people cant take a joke.....

On paper the Northstar is a great engine, just like 09 gtr. It sounds good but doesn't perform and the quality is poor, ex oil and cooling systems. Yes the sc Northstar is more powerful than the 03/04 mod motors, but the Northstar isnt competing with that motor. However, the dohc Northstar is blown away by the competition as i stated before. Cadillac is slowing becoming the standard of the world again. The Northstar was the standard back in 93. Its a 16 year old engine design, even the ls series engines are not that dated. The Northstar engine has no future replacement for a reason.

Here are some quick facts on premium dohc v8s:

2007– Cadillac 4.6 Northstar dohc v8 320 hp @ 6400 RPM

2007- Lexus 4.6 1UR-FSE dohc V8 380 hp @ 6,400 RPM

2007- Mercedes-Benz 5.5 dohc v8 382 @ 6,000 RPM

And you make it sound like I didn't just defend the LSx motors. They are great engines, and have already been honored in '98 and '99 I believe. But honestly the LS9 is an LS3... with a blower. Just like the LS7 is, for all intents and purposes, a bored/stroked LS2. Again, very good motors, just don't fit the criteria. Like the sub-$54,000 entry fee. Not many people are gonna see the benefit of a $70k+ car.


They are not all the same, you have to be dumb to say that LS7-7.0L displacement (427 cubic inches) makes it the largest LS engine offered in a production car. Unlike LS1/LS6, LS2 and LS3 engines, the LS7 uses a Siamese-bore cylinder block design - required for its big, 4.125-inch bores. Competition-proven heads and lightweight components, such as titanium rods and intake valves. The L99 version is equipped with GM's fuel-saving Active Fuel Management cylinder deactivation system . LS9 is the boost version that uses the strengthened similar 6.2L LS3 block but with a stronger rotating assembly, roto-cast cylinder heads and a sixth-generation 2.3L Roots-type supercharger and lower compression.

It's alot more complex than just slapping on a super charger on an LS3 and calling it a day.

LOL at the LT1 bashing..... Some people cant take a joke.....


Haha trust me I'm not getting emotional over the northstar of all engines... Can't get over the quality issues of the northstar thats the truth.

I personally liked the lt1 comment :punch:

They are not all the same, you have to be dumb to say that LS7-7.0L displacement (427 cubic inches) makes it the largest LS engine offered in a production car. Unlike LS1/LS6, LS2 and LS3 engines, the LS7 uses a Siamese-bore cylinder block design - required for its big, 4.125-inch bores. Competition-proven heads and lightweight components, such as titanium rods and intake valves. The L99 version is equipped with GM's fuel-saving Active Fuel Management cylinder deactivation system . LS9 is the boost version that uses the strengthened similar 6.2L LS3 block but with a stronger rotating assembly, roto-cast cylinder heads and a sixth-generation 2.3L Roots-type supercharger and lower compression.

It's alot more complex than just slapping on a super charger on an LS3 and calling it a day.

Titanium rods are NOTHING new... used first on the NSX I believe back in 1991. So again, nothing revolutionary. They are both fantastic motors, but don't meet the criteria for the competition. You have no reason to defend the motors to me.

Here are some quick facts on premium dohc v8s:

2007– Cadillac 4.6 Northstar dohc v8 320 hp @ 6400 RPM

2007- Lexus 4.6 1UR-FSE dohc V8 380 hp @ 6,400 RPM

2007- Mercedes-Benz 5.5 dohc v8 382 @ 6,000 RPMYes, that's now maybe....but now go back and look at that list WAY BACK when the Northstar first came out in 1992.
None of those other brands were even close to 300hp.

In an ironic turn of events, Cadillac and that Northstar are actually what helped push Toyota, Mercedes and BMW to improve their numbers. :D

Yep, hence why worldwide competition helps the industry as a whole. If there was no competition, there would be no reason to improve anything.

So again, nothing revolutionary. They are both fantastic motors, but don't meet the criteria for the competition. You have no reason to defend the motors to me.

The motors listed offer no revolutinary break throughts, and the NSX is legendary for being the most under powered car ever,pound for pound the best motor value on earth is the Lsx IMO, I dont care about OHC super intelligent variable valve set-ups.......

pushrod motors =
are proven 56 year history
easy to maintain
lighter
versitle(marine,towing,flex fuel,hybrid,racing,daily driver, over 25mpg)reliable and they work

I would easily take an Lsx over these motors any day when you compare the massive aftermarket support its not even close

*Audi AG: 2.0L TFSI turbocharged DOHC I-4 (A4 Avant)
* BMW AG: 3.0L turbocharged DOHC I-6 (135i Coupe)
* BMW AG: 3.0L DOHC I-6 Turbodiesel (335d)
* Chrysler LLC: 5.7L Hemi OHV V-8 (Dodge Ram/Challenger R/T)

But im talking to a ford guy that has not driven or owned any of those motors..and wouldnt know anything about long term performance,reliability or cost of owner ship and maintenence

I have owned and driven on a daily basis- sbc,sbf,Gen I tpi,Gen II LT-1,ford 32 valve v-8 cobra,5.7 liter HEMI,Gen III ls-1,GEN IV LS2/LS3,BMW I4,Chrysler DOHC V-6,DSM gen I

The motors listed offer no revolutinary break throughts, and the NSX is legendary for being the most under powered car ever,pound for pound the best motor value on earth is the Lsx IMO, I dont care about OHC super intelligent variable valve set-ups.......

pushrod motors =
are proven 56 year history
easy to maintain
lighter
versitle(marine,towing,flex fuel,hybrid,racing,daily driver, over 25mpg)reliable and they work

I would easily take an Lsx over these motors any day when you compare the massive aftermarket support its not even close

*Audi AG: 2.0L TFSI turbocharged DOHC I-4 (A4 Avant)
* BMW AG: 3.0L turbocharged DOHC I-6 (135i Coupe)
* BMW AG: 3.0L DOHC I-6 Turbodiesel (335d)
* Chrysler LLC: 5.7L Hemi OHV V-8 (Dodge Ram/Challenger R/T)

But im talking to a ford guy that has not driven or owned any of those motors..and wouldnt know anything about long term performance,reliability or cost of owner ship and maintenence

I have owned and driven on a daily basis- sbc,sbf,Gen I tpi,Gen II LT-1,ford 32 valve v-8 cobra,5.7 liter HEMI,Gen III ls-1,GEN IV LS2/LS3,BMW I4,Chrysler DOHC V-6,DSM gen I

OHV engines have the camshaft below the cylinder head, and thus use lifters and pushrods to help actuate the valves that are in the cylinder head. Compared to OHC engines, they allow for better packaging, but are less efficient compared to OHC designs due to increased valvetrain mass. To open a valve, the camshaft pushes on a lifter, which pushes a pushrod, which pushes on a rocker am, which opens the valve. OHC engines don't have the weight of the pushrod to overcome. While the weight of a pushrod & lifter is seemingly insignificant, when you consider it can account for more than 15% of the valvetrain mass, and it has to open a valve up to 6000 times a minute (or more), it adds up to measurable difference. It's all about inertia - the less weight it has to move, the less energy is required to open the valve, and thus, there is more energy that can be transferred to the crankshaft - meaning more HP to the wheels.

What makes the OHV design look efficient on paper, has relatively nothing to do with the design of the motor, but moreso with the transmissions gearing. Given equal displacement DOHC will make more power 99% of the time over a wider rpm range.

Porsche 3.6 liter - 415hp n/a
M5 5.0 liter 500hp
Viper(range) 8-8.3 liter 500hp-600hp
350z 3.5-3.7 liter 332hp
ls1 5.7 liter 350hp

Secondly, DOHC allows you to utilize VVT on both intake and exhaust side of the cams.

OHV engines have the camshaft below the cylinder head.

OHC engines are also OHV engines. OHV means that the valves are over the piston, not next to it in the block, like a flathead. Most people, including manufacturers, use the same definition you did but in actuality its not accurate. But yea OHC engines are usually more efficient than conventional cam in block engines.

Porsche 3.6 liter - 415hp n/a
M5 5.0 liter 500hp
Viper(range) 8-8.3 liter 500hp-600hp
350z 3.5-3.7 liter 332hp
ls1 5.7 liter 350hp

Secondly, DOHC allows you to utilize VVT on both intake and exhaust side of the cams.


I think the viper motor is a bad example since it is an 8.3 liter v-10 with no vvt....in terms of power to weight ratio

OHV engines have the camshaft below the cylinder head, and thus use lifters and pushrods to help actuate the valves that are in the cylinder head. Compared to OHC engines, they allow for better packaging, but are less efficient compared to OHC designs due to increased valvetrain mass. To open a valve, the camshaft pushes on a lifter, which pushes a pushrod, which pushes on a rocker am, which opens the valve. OHC engines don't have the weight of the pushrod to overcome. While the weight of a pushrod & lifter is seemingly insignificant, when you consider it can account for more than 15% of the valvetrain mass, and it has to open a valve up to 6000 times a minute (or more), it adds up to measurable difference. It's all about inertia - the less weight it has to move, the less energy is required to open the valve, and thus, there is more energy that can be transferred to the crankshaft - meaning more HP to the wheels.

What makes the OHV design look efficient on paper, has relatively nothing to do with the design of the motor, but moreso with the transmissions gearing. Given equal displacement DOHC will make more power 99% of the time over a wider rpm range.

Porsche 3.6 liter - 415hp n/a
M5 5.0 liter 500hp
Viper(range) 8-8.3 liter 500hp-600hp
350z 3.5-3.7 liter 332hp
ls1 5.7 liter 350hpOk, we covered the horsepower end of that spectrum.
Now let's talk about torque. :D ;)

The motors listed offer no revolutinary break throughts, and the NSX is legendary for being the most under powered car ever,pound for pound the best motor value on earth is the Lsx IMO, I dont care about OHC super intelligent variable valve set-ups.......

pushrod motors =
are proven 56 year history
easy to maintain
lighter
versitle(marine,towing,flex fuel,hybrid,racing,daily driver, over 25mpg)reliable and they work

I would easily take an Lsx over these motors any day when you compare the massive aftermarket support its not even close

*Audi AG: 2.0L TFSI turbocharged DOHC I-4 (A4 Avant)
* BMW AG: 3.0L turbocharged DOHC I-6 (135i Coupe)
* BMW AG: 3.0L DOHC I-6 Turbodiesel (335d)
* Chrysler LLC: 5.7L Hemi OHV V-8 (Dodge Ram/Challenger R/T)

But im talking to a ford guy that has not driven or owned any of those motors..and wouldnt know anything about long term performance,reliability or cost of owner ship and maintenence

I have owned and driven on a daily basis- sbc,sbf,Gen I tpi,Gen II LT-1,ford 32 valve v-8 cobra,5.7 liter HEMI,Gen III ls-1,GEN IV LS2/LS3,BMW I4,Chrysler DOHC V-6,DSM gen I
I don't know why you feel compelled to turn everything into an attempted personal attack. I've driven (on a regular basis) mod motors, LT1s, LS1s, VQ30DEs, crappy pushrod Ford V6s, several Honda 4cyls, Honda V6s, etc. Not every car can have a V8, which is where most of the motors on that list come into play. You say you would "take an lsx over any of them," but with most of those cars it's not even an option. And I do know about long term performance/reliability and cost of ownership/maintenance, thank you very much. I know that I BOUGHT my first car ('94 Integra GS-R) with 134k miles on it with absolutely no qualms. Sold it @ 193k miles, and the only maintenance that had to be done on the car the whole time was a new clutch and a timing belt. And then I know about my mom's old LT1 Vette that had the transmission blow @ 114k miles (which the mechanic said was "about right"), and then the Optispark went south. And yes the transmission on my sister's '99 TL went bad @ 97k miles, but it was covered by Honda. So my experience with some of these "high-tech" motors is that they are VERY good. Just like the LSx is very good, for different reasons.

Edit: And I am in NO way a "Ford guy." I'm pretty sure we've been over this before.

Yes, that's now maybe....but now go back and look at that list WAY BACK when the Northstar first came out in 1992.
None of those other brands were even close to 300hp.

In an ironic turn of events, Cadillac and that Northstar are actually what helped push Toyota, Mercedes and BMW to improve their numbers. :D

Totally true, Cadillac line represents the best of the best from GM and the competitors obviously figured out a way to beat GM/Cadillac. Cadillac a few years ago was a boring brand. Cadillac is becoming the standard of the world again if they keep up the good work.

Cadillac a few years ago was a boring brand. Cadillac is becoming the standard of the world again if they keep up the good work.:werd: The new CTS-V (even the entire CTS line in general) is an amazing performance/sports sedan. :thumb:

:werd: The new CTS-V (even the entire CTS line in general) is an amazing performance/sports sedan. :thumb:

Of course, its a 4 door vette. The cts was a breakthrough for Cadillac.

I think the viper motor is a bad example since it is an 8.3 liter v-10 with no vvt....in terms of power to weight ratio

The Viper does have VVT.

Ok, we covered the horsepower end of that spectrum.
Now let's talk about torque. :D ;)

What about it? If we're comparing displacement in terms of power/torque then your argument is mute. Considering the examples that I gave you, I think the correlation should be hp to weight.

OHV engines have the camshaft below the cylinder head, and thus use lifters and pushrods to help actuate the valves that are in the cylinder head. Compared to OHC engines, they allow for better packaging, but are less efficient compared to OHC designs due to increased valvetrain mass. To open a valve, the camshaft pushes on a lifter, which pushes a pushrod, which pushes on a rocker am, which opens the valve. OHC engines don't have the weight of the pushrod to overcome. While the weight of a pushrod & lifter is seemingly insignificant, when you consider it can account for more than 15% of the valvetrain mass, and it has to open a valve up to 6000 times a minute (or more), it adds up to measurable difference. It's all about inertia - the less weight it has to move, the less energy is required to open the valve, and thus, there is more energy that can be transferred to the crankshaft - meaning more HP to the wheels.

What makes the OHV design look efficient on paper, has relatively nothing to do with the design of the motor, but moreso with the transmissions gearing. Given equal displacement DOHC will make more power 99% of the time over a wider rpm range.

Porsche 3.6 liter - 415hp n/a
M5 5.0 liter 500hp
Viper(range) 8-8.3 liter 500hp-600hp
350z 3.5-3.7 liter 332hp
ls1 5.7 liter 350hp

Secondly, DOHC allows you to utilize VVT on both intake and exhaust side of the cams.
If HP/L wasn't used as a basis for taxation in Europe, do you really think that the European automakers would have made the decisions they've made and gone down the path that they've gone down? HP/L is a nice number to look at on paper, but it's absolutely meaningless in the real world.

I'm sure the M5's 5.0L V10 is considerably larger and heavier than the LS7 in the Z06. Each has roughly the same output, but which engine has the advantage? The LS7. It's smaller, lighter, and slightly more powerful.

Also, I think you made an error with your valve openings per minute calculation. Each valve opens once for every 2 revolutions the engine makes. Not sure what pushrod engine you're spinning to 12k.

If HP/L wasn't used as a basis for taxation in Europe, do you really think that the European automakers would have made the decisions they've made and gone down the path that they've gone down? HP/L is a nice number to look at on paper, but it's absolutely meaningless in the real world.

I'm sure the M5's 5.0L V10 is considerably larger and heavier than the LS7 in the Z06. Each has roughly the same output, but which engine has the advantage? The LS7. It's smaller, lighter, and slightly more powerful.

Also, I think you made an error with your valve openings per minute calculation. Each valve opens once for every 2 revolutions the engine makes. Not sure what pushrod engine you're spinning to 12k.

OF course the M5 would be larger and heavier considering it is a V10. The point I'm trying to advocate here is, the use of technology to overcome displacement. Given the same displacement, DOHC motors will make more power over a broader rpm range.

OF course the M5 would be larger and heavier considering it is a V10. The point I'm trying to advocate here is, the use of technology to overcome displacement. Given the same displacement, DOHC motors will make more power over a broader rpm range.
The ONLY advantage OHC has over pushrods is that it's easier for the engine to rev higher due to a lighter valvetrain. For the same displacement, pushrod engines are smaller and lighter. With a good head and the right cam, you can make the same power as an OHC engine up to 6000-6500rpm before the valvetrain starts to become a considerable limitation. The way I see it, there's no reason to have, for a street application, an engine that revs to 9000rpm to make X hp when you can use a little bit more displacement and/or forced induction to make the same horsepower at a lower rpm. There is no bad aspect to having an engine that is physically smaller and lighter with the same power numbers.

And for all that technology that BMW used to get 500hp out of their 5.0L V10, it still gets 12/18 mpg. There's no official mileage figures out for the 6.2L supercharged CTS-V, but I'd be willing to bet that it gets a bit more than 12/18, and with 50 more horsepower to boot.

I'll reiterate. The only real reason that European auto manufacturers build small displacement high revving engines is to minimize taxes while not being unbearably slow.

The ONLY advantage OHC has over pushrods is that it's easier for the engine to rev higher due to a lighter valvetrain. For the same displacement, pushrod engines are smaller and lighter. With a good head and the right cam, you can make the same power as an OHC engine up to 6000-6500rpm before the valvetrain starts to become a considerable limitation. The way I see it, there's no reason to have, for a street application, an engine that revs to 9000rpm to make X hp when you can use a little bit more displacement and/or forced induction to make the same horsepower at a lower rpm. There is no bad aspect to having an engine that is physically smaller and lighter with the same power numbers.

And for all that technology that BMW used to get 500hp out of their 5.0L V10, it still gets 12/18 mpg. There's no official mileage figures out for the 6.2L supercharged CTS-V, but I'd be willing to bet that it gets a bit more than 12/18, and with 50 more horsepower to boot.

I'll reiterate. The only real reason that European auto manufacturers build small displacement high revving engines is to minimize taxes while not being unbearably slow.

The gas mileage has more to due with the trans being 1:1 in 4th and for allowing 5th and 6th gears to be over drives. This is what you sacrifice when doing this(BMW has 60 more hp, but 700lbs more weight):

http://www.youtube.com/watch?v=9_QpKNozKN0

The reason why its best to have torque in the higher rpms(more hp), instead of down low is to take advantage of gearing.

And if pushrod motor where so efficient, why hasn't GM or Dodge incorporated this into their 4cyl motors? Why does the new Caddy(6cyl) have DOHC?

The gas mileage has more to due with the trans being 1:1 in 4th and for allowing 5th and 6th gears to be over drives. This is what you sacrifice when doing this(BMW has 60 more hp, but 700lbs more weight):

http://www.youtube.com/watch?v=9_QpKNozKN0

The reason why its best to have torque in the higher rpms(more hp), instead of down low is to take advantage of gearing.

And if pushrod motor where so efficient, why hasn't GM or Dodge incorporated this into their 4cyl motors? Why does the new Caddy(6cyl) have DOHC?
Pushrod engines are more efficient only on V-engines, I hope to god you have figured this out by now.
And GM themselves have stated they have OHC v-engines as marketing:
http://www.caranddriver.com/features/columns/c_d_staff/larry_webster/the_pushrod_engine_finally_gets_its_due_column
So if the pushrod design makes such a good V-8, why does GM make a DOHC V-8 Northstar? "I'm not going to touch that one," laughs Winegarden. GM's party line is that some customers want what it calls "high-feature engines."

Pushrod engines are more efficient only on V-engines, I hope to god you have figured this out by now.
And GM themselves have stated they have OHC v-engines as marketing:
http://www.caranddriver.com/features/columns/c_d_staff/larry_webster/the_pushrod_engine_finally_gets_its_due_column

Its not the motor that makes the mpg efficient, its the gearing of the trans!

Are you forgetting that the LT5 was the motor of the day in the Vette.

1990-92 1993-1995

SAE Net Power 375 hp @ 6,000 rpm 405 hp @ 5,800 rpm
SAE Net Torque 370 ft lbs @ 4800 rpm 385 ft lbs @ 4800 rpm
Compression Ratio 11:1 11:1


Big numbers for 18 yrs ago

Its not the motor that makes the mpg efficient, its the gearing of the trans!

Did I say anything about gas mileage?

Are you forgetting that the LT5 was the motor of the day in the Vette.

1990-92 1993-1995

SAE Net Power 375 hp @ 6,000 rpm 405 hp @ 5,800 rpm
SAE Net Torque 370 ft lbs @ 4800 rpm 385 ft lbs @ 4800 rpm
Compression Ratio 11:1 11:1


Big numbers for 18 yrs ago

LT5 - 405hp/385ft.lbs 630lbs
LS6 - 405hp/400ft.lbs 390lbs
Oops...
Do you want to talk about cost and physical size too? There is a reason they stuck with the pushrod engine...

Did I say anything about gas mileage?


LT5 - 405hp/385ft.lbs 630lbs
LS6 - 405hp/400ft.lbs 390lbs
Oops...
Do you want to talk about cost and physical size too? There is a reason they stuck with the pushrod engine...

Where are the weights for the motors? Link? What about cost? The Z06 is 70k new and the ZR1 is 120k new. I don't think cost is that much of an issue considering the cost of the cars. Again, given the same displacement DOHC will make more power, torque throughout a longer rpm range.

Again, given the same displacement DOHC will make more power, torque throughout a longer rpm range.
I think that's more a result of the camming and, to a lesser extent, 4 valves per cylinder.

The Z06 is 70k new and the ZR1 is 120k new. I don't think cost is that much of an issue considering the cost of the cars.
1 cam, 1 cam gear, 1 timing chain, 16 pushrods, and 16 valves are cheaper than 4 cams, 4 cam gears, 2 (much longer) timing chains, and 32 valves. How much more would the Z06 and ZR1 have been if they used OHC engines? Not sure, but it certainly would have been more. And how can you say cost was not much of a factor? Cost is always a factor, especially for the Corvette which is known for its bang per buck. You can only engineer what the accounting department will pay for.

I think that's more a result of the camming and, to a lesser extent, 4 valves per cylinder.


1 cam, 1 cam gear, 1 timing chain, 16 pushrods, and 16 valves are cheaper than 4 cams, 4 cam gears, 2 (much longer) timing chains, and 32 valves. How much more would the Z06 and ZR1 have been if they used OHC engines? Not sure, but it certainly would have been more. And how can you say cost was not much of a factor? Cost is always a factor, especially for the Corvette which is known for its bang per buck. You can only engineer what the accounting department will pay for.

The price can be negated if the production numbers are there. Supply and Demand can cut the cost down significantly.

Its deeper than just 4 valves per cylinder. Its the ability to change cam timing on both the intake and exhaust cams. Therefor a higher degree of tuning can be implimented. You also have a more efficient combustion since the spark plug is placed in the middle of the combustion chamber.

Where are the weights for the motors? Link?

http://www.gilbertautoparts.com/ChevySmallBlockV8s/LS1.cfm
http://www.corvetteactioncenter.com/forums/lt4-forum/15290-lt-5-vs-lt1-lt4-weight.html
http://www.whiteracingproducts.com/index.php?main_page=product_info&cPath=10_210&products_id=1114


What about cost? The Z06 is 70k new and the ZR1 is 120k new.

Are you seriously that dense? Cost of the engines... A brand new LS2 can be bought for a little over $5,000, while the LT5 when new went in the $20Ks.
And the C6 ZR1 is $106,000 new, nice try though.


I don't think cost is that much of an issue considering the cost of the cars.

Check on the as new price of the C4 ZR1 compared to the C4 Z51, and then compare that to the C5 Z06...

Again, given the same displacement DOHC will make more power, torque throughout a longer rpm range.
Then why does the LS6 make the same power (and more torque through out the whole rev range) than the LT5 with the same displacement? Your argument is flawed and moronic. A DOHC engine is only going to make more power/torque if it is tuned to do so, your making it sound like it magically gains power from the OHCs.

The price can be negated if the production numbers are there. Supply and Demand can cut the cost down significantly.
The production numbers for the Z06 and ZR1 are low enough that cost is likely a high factor.

Its deeper than just 4 valves per cylinder. Its the ability to change cam timing on both the intake and exhaust cams. Therefor a higher degree of tuning can be implimented. You also have a more efficient combustion since the spark plug is placed in the middle of the combustion chamber.
You can do that kind of tuning with cam-in-block engines as well, it's just harder. You have to grind a new cam instead of a new timing gear.

tuned [/I]to do so, your making it sound like it magically gains power from the OHCs.
In all fairness, the oldest LS6 is still 11 years newer than the release of the LT5. OHC is a more efficient design, but it doesn't mean that every OHC motor will make more power than a pushrod motor.
The production numbers for the Z06 and ZR1 are low enough that cost is likely a high factor.


You can do that kind of tuning with cam-in-block engines as well, it's just harder. You have to grind a new cam instead of a new timing gear.

The point was the ability to do variable valve timing, not just change the timing.

In all fairness, the oldest LS6 is still 11 years newer than the release of the LT5. OHC is a more efficient design, but it doesn't mean that every OHC motor will make more power than a pushrod motor.
Exactly my point.
In a racing application where a car would be making north of 1000hp+ I wouldn't mind a V-DOHC engine because the added weight would really be minuscule compared to the power/torque its making. But for the 99.9% rest of the world with street performance cars, a V-OHV engine is more efficient because of weight, size, and cost.

http://www.gilbertautoparts.com/ChevySmallBlockV8s/LS1.cfm
http://www.corvetteactioncenter.com/forums/lt4-forum/15290-lt-5-vs-lt1-lt4-weight.html
http://www.whiteracingproducts.com/index.php?main_page=product_info&cPath=10_210&products_id=1114


Are you seriously that dense? Cost of the engines... A brand new LS2 can be bought for a little over $5,000, while the LT5 when new went in the $20Ks.
And the C6 ZR1 is $106,000 new, nice try though.


Check on the as new price of the C4 ZR1 compared to the C4 Z51, and then compare that to the C5 Z06...

Then why does the LS6 make the same power (and more torque through out the whole rev range) than the LT5 with the same displacement? Your argument is flawed and moronic. A DOHC engine is only going to make more power/torque if it is tuned to do so, your making it sound like it magically gains power from the OHCs.

The weight is 596lbs(page two fully dressed)

The MSRP on the ZR1 is 103,xxx without any options. Show me one person that paid 103k :eyes:

http://www.automotive.com/2009/101/chevrolet/corvette/zr1-coupe/3045/pricing/index.html

Its funny you want to bring up the price of a motor when the LS7 is 14k new lol

The weight is 596lbs(page two fully dressed)
The MSRP on the ZR1 is 103,xxx without any options. Show me one person that paid 103k :eyes:

http://www.automotive.com/2009/101/chevrolet/corvette/zr1-coupe/3045/pricing/index.html

Show me one person that paid $70,000 for a GTR :eyes:


Its funny you want to bring up the price of a motor when the LS7 is 14k new lol
For a 505hp/470ft.lbs, 440lbs engine with dry sump thats really not that bad of a deal.

Weight is 390lbs out of crate.
http://www.gilbertautoparts.com/ChevySmallBlockV8s/LS1.cfm


Show me one person that paid $70,000 for a GTR :eyes:


For a 505hp/470ft.lbs, 440lbs engine with dry sump thats really not that bad of a deal.

I know two people that purchased their gtr at Baker Jackson Nissan(Brad) is the manager and the only one that deals with the GTR. And the MSRP is 83k now, not 73k like it was(which they bought at msrp). Nissan went up on the price.

Show me one person that paid $70,000 for a GTR :eyes:


For a 505hp/470ft.lbs, 440lbs engine with dry sump thats really not that bad of a deal.

Not that bad of a deal, but you're where just complaining about cost :eyes:

Its funny you want to bring up the price of a motor when the LS7 is 14k new lolIt's only $12,800.00 (including freight) for the smart shoppers but still. :)
And that's a lot of motor for that money.

Exactly my point.
In a racing application where a car would be making north of 1000hp+ I wouldn't mind a V-DOHC engine because the added weight would really be minuscule compared to the power/torque its making. But for the 99.9% rest of the world with street performance cars, a V-OHV engine is more efficient because of weight, size, and cost.

I'd say that OHC V6s are the industry standard now... Ford/GM/Mopar agrees. The applications where people want smoothness basically require OHC engines now to compete.

Back to pushrod vs dohc:

Lets clarify this a little bit. First of all, the 1993 lt1 produced 300hp@5000rpm and 340lb-ft@3600rpm. It wasn't until 96 that the lt4 produced 330hp. The lt5 in the 93 zr1 produced 405hp@5900rpm and 400lb-ft@4000rpm. Now that we're comparing apples to apples, there is a 105hp and 60lb-ft difference in output, let alone a narrower powerband, all from the same displacement.

As a matter of fact, now the difference in output is a staggering 35% and in torque 17.6%. If that is not a significant figure, I don't know what is. Ironically, these two engines were put in the same chassis side by side and both corvettes, so i don't see how any vette fan could be biased towards one or the other either.

Fact of matter is, it wasn't until 10 years after the first ZR1 that chevrolet matched the output of the powerplant with the ls6.

Consider this and you would get an idea of what chevy could come up with if they were to consider another dohc v8 for the vette.

I know two people that purchased their gtr at Baker Jackson Nissan(Brad) is the manager and the only one that deals with the GTR. And the MSRP is 83k now, not 73k like it was(which they bought at msrp). Nissan went up on the price.

My friend's brother's roomate's uncle knows a guy who bought a ZR1 for MSRP.

Not that bad of a deal, but you're where just complaining about cost :eyes:

Yes, because 405hp LS6 = $7,000ish and 405hp LT5 (new) = $20,000ish.

My friend's brother's roomate's uncle knows a guy who bought a ZR1 for MSRP.



Yes, because 405hp LS6 = $7,000ish and 405hp LT5 (new) = $20,000ish.

I highly doubt an LT5 was 20k in the early 90's

My friend's brother's roomate's uncle knows a guy who bought a ZR1 for MSRP.



Yes, because 405hp LS6 = $7,000ish and 405hp LT5 (new) = $20,000ish.

His name is Brad at Baker Jackson in Houston. Call em.

http://www.mulsannescorner.com/moparv8.html
http://www.mulsannescorner.com/mugenv8.html

Most racing dohc motors are just as light as pushrod motors. So the tech is there.

Consider this and you would get an idea of what chevy could come up with if they were to consider another dohc v8 for the vette.Yes, they'd then have a motor that 1) weighs more (more weight = less fuel economy), 2) is physically larger (meaning a less aerodynamic body to put it in = again less fuel efficiency and potentially slower top speeds) and 3) costs more to produce (potentially lower sales).

GM/Chevrolet doesn't use that OHV design by accident or because they don't have enough engineering prowess (because they do)...they use it because they weighed all of their objectives and needs and intentionally chose to use an OHV design.

I'd say that OHC V6s are the industry standard now... Ford/GM/Mopar agrees. The applications where people want smoothness basically require OHC engines now to compete.

I agree they are the industry standard but for different reasons (marketing). "Smoothnes", NVH, feel, all have much more to do with the car and how its built than the engine (motor mounts, firewall, exhaust, transmission, where the engine is mounted etc. etc.). I've driven plenty of OHV's and OHC engines of various displacements and cylinders and can tell you OHC's are not automatically smoother with less NVH. As I'm sure you know the LS6 in the Gen 1 CTS-V is identical to the LS6 in the C5 Z06, but magically the CTS-V's LS6 felt smoother and had less NVH. That same LS6 was also smoother, with less NVH (ignoring the louder exhaust note) than the base CTS's 3.2L DOHC V6. And that same V6 feels no smoother than GM's 3600 OHV V6 (although its more 'crisp' IMO).

Yes, they'd then have a motor that 1) weighs more (more weight = less fuel economy), 2) is physically larger (meaning a less aerodynamic body to put it in = again less fuel efficiency and potentially slower top speeds) and 3) costs more to produce (potentially lower sales).

GM/Chevrolet doesn't use that OHV design by accident or because they don't have enough engineering prowess (because they do)...they use it because they weighed all of their objectives and needs and intentionally chose to use an OHV design.

-You are speculating that the increase in weight, could not be negated through the chassis.

-If they use the same trans/gearing, the LT5 would be more fuel efficient

-why would the top speed be less, it would be more with the same exact setup and gearing.

We will see what the future holds for the vette. But I guarantee you in the near future, it will be dohc design. Just like the new V6 Caddies

Back to pushrod vs dohc:

Lets clarify this a little bit. First of all, the 1993 lt1 produced 300hp@5000rpm and 340lb-ft@3600rpm. It wasn't until 96 that the lt4 produced 330hp. The lt5 in the 93 zr1 produced 405hp@5900rpm and 400lb-ft@4000rpm. Now that we're comparing apples to apples, there is a 105hp and 60lb-ft difference in output, let alone a narrower powerband, all from the same displacement.

As a matter of fact, now the difference in output is a staggering 35% and in torque 17.6%. If that is not a significant figure, I don't know what is. Ironically, these two engines were put in the same chassis side by side and both corvettes, so i don't see how any vette fan could be biased towards one or the other either.

Fact of matter is, it wasn't until 10 years after the first ZR1 that chevrolet matched the output of the powerplant with the ls6.

Consider this and you would get an idea of what chevy could come up with if they were to consider another dohc v8 for the vette.

I think we should go back to these points. It took GM 10 years to surpass what the LT5 did. 105hp difference with the same displacement. I think this about sums it up.

Yes, they'd then have a motor that 1) weighs more (more weight = less fuel economy), 2) is physically larger (meaning a less aerodynamic body to put it in = again less fuel efficiency and potentially slower top speeds) and 3) costs more to produce (potentially lower sales).

GM/Chevrolet doesn't use that OHV design by accident or because they don't have enough engineering prowess (because they do)...they use it because they weighed all of their objectives and needs and intentionally chose to use an OHV design.

The discussion, however, is not about the IMMEDIATE need for dohc V8 power for gm, but the possibility down the road when their pushrod designs are starting to fall short.

The mugen to mopar example was made to clarify my point that dohc engines can and are made compact and lightweight, but that for now it is limited due to material usage and cost. 20 years ago, carbon fibres and space age alloys were seldom seen in anything non exotic, but these days they are much more common (specially the alloys) and this trend will continue.

I agree they are the industry standard but for different reasons (marketing). "Smoothnes", NVH, feel, all have much more to do with the car and how its built than the engine (motor mounts, firewall, exhaust, transmission, where the engine is mounted etc. etc.). I've driven plenty of OHV's and OHC engines of various displacements and cylinders and can tell you OHC's are not automatically smoother with less NVH. .

Yep, Driven a VW, Mopar or some newer Hondas with OHC? Not smooth at all. Driven a push rod Cadillac? Can't even tell it is running. Marketing is the only thing that makes it better.
Remeber OHC is old too. 1913ish and used in production in the 20's
GM had straight OHC 6s in the 60's.
That debate is crazy, the one that makes the most power with the least moving parts wins.

-If they use the same trans/gearing, the LT5 would be more fuel efficientNow you're the one that's speculating. ;)






-why would the top speed be lessWhy? Because generally speaking, a DOHC/32+ valve motor of the same displacement will be physically larger (4.6L DOHC Cobra motor is larger than the 5.0L OHV...LT5 is larger than the LSx etc.) than the current Gen III/IV GM V8s and wouldn't fit under the hood/between the inner fenderwells of the current Corvette thus creating the need to increase the vehicle's width and hood height...all else being equal.

Yep, Driven a VW, Mopar or some newer Hondas with OHC? Not smooth at all. Driven a push rod Cadillac? Can't even tell it is running. Marketing is the only thing that makes it better.
Remember OHC is old too. 1913ish and used in production in the 20'sThat's what I find somewhat ironic...so many people tend to classify the typical OHC design as being more "high tech" or more contemporary when in fact it is an older technology then the OHV design LOL. :D

Now you're the one that's speculating. ;)






Why? Because generally speaking, a DOHC/32+ valve motor of the same displacement will be physically larger (4.6L DOHC Cobra motor is larger than the 5.0L OHV...LT5 is larger than the LSx etc.) than the current Gen III/IV GM V8s and wouldn't fit under the hood/between the inner fenderwells of the current Corvette thus creating the need to increase the vehicle's width and hood height...all else being equal.


There's no speculating is the motor is more efficient(105hp and 60lbft more) given the same displacement as the LT1.

The LT5 in the Vette has the same dimensions as the LT1 Vette.

Yep, Driven a VW, Mopar or some newer Hondas with OHC? Not smooth at all. Driven a push rod Cadillac? Can't even tell it is running. Marketing is the only thing that makes it better.
Remeber OHC is old too. 1913ish and used in production in the 20's
GM had straight OHC 6s in the 60's.
That debate is crazy, the one that makes the most power with the least moving parts wins.
What OHC Hondas have you driven that weren't smooth? Even the S2000 is relatively smooth. And my sister's old 3.2TL was buttah-smooth.
Now you're the one that's speculating. ;)






Why? Because generally speaking, a DOHC/32+ valve motor of the same displacement will be physically larger (4.6L DOHC Cobra motor is larger than the 5.0L OHV...LT5 is larger than the LSx etc.) than the current Gen III/IV GM V8s and wouldn't fit under the hood/between the inner fenderwells of the current Corvette thus creating the need to increase the vehicle's width and hood height...all else being equal.

They didn't have to make those changes with the ZR1...

Wasnt the LT5 considered a failure?

What OHC Hondas have you driven that weren't smooth? Even the S2000 is relatively smooth. And my sister's old 3.2TL was buttah-smooth.


They didn't have to make those changes with the ZR1...

Beat you to it :D

Wasnt the LT5 considered a failure?

Nope...

The 2.4 4cyl accord. I had a rental with 8200 miles on it.
Not smooth at all and with the AC it was horrid. I had to drive that turd 1200 miles.

Wasnt the LT5 considered a failure?

The ZR-1 came at the wrong time... it reached it's zenith as the American sports-car market was failing. Did you know that originally the C5 was supposed to be introduced in 1993, but had to be pushed back all the way to 1997 because of budget cuts?

The 2.4 4cyl accord. I had a rental with 8200 miles on it.
Not smooth at all and with the AC it was horrid. I had to drive that turd 1200 miles.

It was a rental. I beat the shiet out of em.

The 2.4 4cyl accord. I had a rental with 8200 miles on it.
Not smooth at all and with the AC it was horrid. I had to drive that turd 1200 miles.

I'll agree they ain't very powerful (especially if you're used to a fast car), but did you ever think that maybe part of the issue with it was that it was a RENTAL car?

With 8200 miles? It is beat?
I guess Honda does make shit then eh?
I mentioned this on a another fourm I frequent and two other folks said had the same type of experience. One of them owns ones.
www.carnuts.us

-You are speculating that the increase in weight, could not be negated through the chassis.
Why compensate though? Lighter = better no matter how you want to argue.

-If they use the same trans/gearing, the LT5 would be more fuel efficient

Then why did the LT5 get the same gas mileage as the LT1?


-why would the top speed be less, it would be more with the same exact setup and gearing.

Why would it be more given the same setup?


We will see what the future holds for the vette. But I guarantee you in the near future, it will be dohc design. Just like the new V6 Caddies
There would be no point. Unfortunately the C6 ZR1 will be the most powerful Corvette we will see for a long time, and if they are not making stupid big power there is no reason to add weight, cost, complexity and size and not gain anything but marketing from it.

Anything can be destroyed if you beat on it hard enough and don't take care of it. 8200 miles of retardedly-bad driving is gonna be pretty tough on a car if the oil isn't changed. But I'm not gonna try and make excuse for it, cuz I wasn't there and neither of us know the conditions that the car was normally driven in.

I think we should go back to these points. It took GM 10 years to surpass what the LT5 did. 105hp difference with the same displacement. I think this about sums it up.

Seriously you do get dumber with each post. GM CHOSE to make a 350hp engine for the C5. Do you think they just all of a sudden discovered "Hey, if we put better flowing exhaust and heads with a slightly bigger cam we can make 400hp!" No. They CHOSE to make a 405hp LS6, its stupid easy to get more power out of it.
This is as dumb as saying that the Japanese couldn't make an engine with more than 280hp. Obviously wrong because they all CHOSE make no more.
GM also CHOSE to go back to the lighter, smaller, more efficient OHV engine after having a DOHC engine. I think this about sums it up.

There's no speculating is the motor is more efficient(105hp and 60lbft more) given the same displacement as the LT1.

The LT5 in the Vette has the same dimensions as the LT1 Vette.

You've obviously never seen under the hood of a ZR1 or LT1 'vette. The LT5 is MASSIVE, and way wider. Seriously just stop while you are ahead.

Why compensate though? Lighter = better no matter how you want to argue.

Then why did the LT5 get the same gas mileage as the LT1?


Why would it be more given the same setup?


There would be no point. Unfortunately the C6 ZR1 will be the most powerful Corvette we will see for a long time, and if they are not making stupid big power there is no reason to add weight, cost, complexity and size and not gain anything but marketing from it.

Dohc has a very significant design advantage. This is not a matter of car comparisons, but simply engine head comparison. dDohc valve positioning allows for better breathing because a)there are two or three individual valves doing the job of 1. This allows for higher flow velocity while flow rate remains and also more efficient flow, because of two or more smaller valves now posing less of a restriction and creating less turbulence. Also, less lift is required to create the same flow rate. That aside, you can now also position the valves much more ideally. Aside from this, one huge valve requires more force to be operated than two smaller ones. The two valves weigh quite a bit less and each require significantly less spring pressure to operate at the same levels of rpm. We also have less reciprocating mass and have only increased the rotating mass slightly. The valvetrain overall is actually lighter and requires less force to operate.

There is also more reciprocating mass (where rotating mass isn't that much of an issue) and this requires even greater spring pressure to limit valve float.

I can go on and on and on about why exactly there are limitations to pushrod engines and i have for many pages. There are apparent design advantages to pushrod units (weight/size) but they can be overcome for dohc engines, where the more efficient and effective breathing of dohc will never be matched by pushrod heads. As good as a pushrod head could be designed, the same level of engineering will yield better end results with a dohc design.


With its technology and manufacturing abilities, gm could easily produce a physically small and light fair displacement V8 to weigh no more than the current ls1/2 and be capable of producing more output than either one of them, with the same, or even lower displacement, while requiring slightly less fuel to do so.

The usable torque that pushrod engines have comes from their lower state of tune(cant revv as easily) and larger displacement. Give a dohc head the same displacement and it will consume the same fuel and breath better at partial throttle(also, the higher intake velocity at partial throttle and lower revvs contributes to a better fuel atomization and more effective pumping in general)and produce more torque everywhere, therefore more power everywhere. This equates to greater EFFICIENCY, more power from the same displacement and consumption, or the same power from less displacement and less fuel consumption.

I would also disagree with a heavier, far larger engine in a vette, producing the same output and adding complexity. Nonetheless, that doesn't outrule the possibility of this powerplant possibly having the same advantages of the lt5, without its disadvantages(which weren't that significant btw).

The lt5 weighed about 50 lbs more than the lt1/4, which isn't that significant at all. These days they could build an engine similar to the lt5, but with a smaller size and lower weight.

Here is a quote from shubeck racing, a premier engine designer for offshore boats etc.

Lets Face the Facts

"Most of the engines used in hi-performance race cars and race boats today, are modified from the engines designed for Detroit production automobiles in the 1950s and 60s.

The engines are based on an overhead valve head design with two valves per cylinder, driven by a single camshaft in the block through varied arrangements of tappets and push rods.

Granted, when first introduced, they were a far cry better than Henry Ford’s Flathead engines, that were in Vogue at the time, but not in step with modern day engine technology.

The American Auto Industry, once known for its world leadership, got left behind with the introduction of more efficient, four valve per cylinder, dual overhead cam engines, built in Europe and Japan.The valve train in Schubeck engines, closely relate to those Mercedes and Honda race engines.

Compare the similarities between Schubeck engines and the engines winning at Lemons and Indy. Starting with the valve train, for example, newer engine designs all use overhead cams proven to be less stressful by doing away with problems related to push rods and tappets. Fewer moving parts mean less reciprocating weight. Less weight helps the valve train operate in all rpm ranges with less effort and more efficiency.

Adding to a more relaxed valve train are the smaller and lighter valves and springs, also requiring less spring pressure to operate. Four valves over two valves per cylinder, affords a greater ability for the engine to breath, thereby increasing the volumetric efficiency for more power.

Topping today's list of reasons for performance engine failures, are broker valve train components. All because they are overstressed. Schubeck's solution to this problem is obvious and simple. Reduce the stress."

http://www.schubeckracing.com/new2/index.php?module=pagemaster&PAGE_user_op=view_page&PAGE_id=12&MMN_position=52:52

According to my sources, the LT5 weighed 39lbs more than the L98.

What OHC Hondas have you driven that weren't smooth? Even the S2000 is relatively smooth. And my sister's old 3.2TL was buttah-smooth.
early 90s Prelude Si, and mid 90s Civic Si. As smooth as a lawnmower. But seriously they were not smooth by any means.


They didn't have to make those changes with the ZR1...
The C4 has a large engine bay.

http://www.zr1netregistry.com/ZR1_specs.htm\

An LT1 is true SBC, well sort of the dimesions are the same. Just reversed cooled and no distributor
http://www.selectric.org/manuals/chevypower/

early 90s Prelude Si, and mid 90s Civic Si. As smooth as a lawnmower. But seriously they were not smooth by any means.


The C4 has a large engine bay.

You completely ignored my post above you.

LOL at your The C4 has a large engine bay.

According to my sources, the LT5 weighed 39lbs more than the L98.

Correct.

Correct.

So JDM wasn't telling the twoof:eyes: What happened to the significant weight advantage?

early 90s Prelude Si, and mid 90s Civic Si. As smooth as a lawnmower. But seriously they were not smooth by any means.


The C4 has a large engine bay.

I've only driven a few Preludes (VTEC models, not an Si), and haven't driven any EG SIs. But my Integra GS-R was quite smooth.

Dohc has a very significant design advantage. This is not a matter of car comparisons, but simply engine head comparison. dDohc valve positioning allows for better breathing because a)there are two or three individual valves doing the job of 1. This allows for higher flow velocity while flow rate remains and also more efficient flow, because of two or more smaller valves now posing less of a restriction and creating less turbulence. Also, less lift is required to create the same flow rate. That aside, you can now also position the valves much more ideally. Aside from this, one huge valve requires more force to be operated than two smaller ones. The two valves weigh quite a bit less and each require significantly less spring pressure to operate at the same levels of rpm. We also have less reciprocating mass and have only increased the rotating mass slightly. The valvetrain overall is actually lighter and requires less force to operate.

There is also more reciprocating mass (where rotating mass isn't that much of an issue) and this requires even greater spring pressure to limit valve float.

I can go on and on and on about why exactly there are limitations to pushrod engines and i have for many pages. There are apparent design advantages to pushrod units (weight/size) but they can be overcome for dohc engines, where the more efficient and effective breathing of dohc will never be matched by pushrod heads. As good as a pushrod head could be designed, the same level of engineering will yield better end results with a dohc design.
Nice copy/paste. But don't bother trying to tell me the advantages of OHC vs pushrod, I know them already.


With its technology and manufacturing abilities, gm could easily produce a physically small and light fair displacement V8 to weigh no more than the current ls1/2 and be capable of producing more output than either one of them, with the same, or even lower displacement, while requiring slightly less fuel to do so.

So this begs the question, why haven't they? Wait... Why hasn't ANY manufacture done this?
Since I know you can't answer this, I will for you. Its BS.
If GM were to produce a DOHC engine that made 405hp again it would be either: Heavier, physically larger, or more expensive than the LSx, or most likely all of the above.
FERRARI, with its high budget builds has not built a powerful DOHC V8 engine that is under 390lbs like the LS2, or LS3. (The 4.3L in the F430 weighs 416lbs).


The usable torque that pushrod engines have comes from their lower state of tune(cant revv as easily) and larger displacement. Give a dohc head the same displacement and it will consume the same fuel and breath better at partial throttle(also, the higher intake velocity at partial throttle and lower revvs contributes to a better fuel atomization and more effective pumping in general)and produce more torque everywhere, therefore more power everywhere. This equates to greater EFFICIENCY, more power from the same displacement and consumption, or the same power from less displacement and less fuel consumption.
But be bigger, weigh more, and cost more.
Power per displacement is not efficiency, that's idiocy. Power to weight is efficiency and power to physical size is efficiency because those are actual real world relevant things to performance. In what way would decreasing the displacement of an engine and extracting the same power out of it as before be beneficial in any way?

If GM is making over 400hp/400ft.lbs of torque from an engine that weighs less than 400lbs, and costs around $5,000 why the hell would you bother trying to make a DOHC engine if all you want is 400hp? TRULLY what REAL WORLD benefits would you see if you wanted to make <500hp production engine for a performance car?
If DOHC engines can supposedly get such better gas mileage, then why don't they beat out the LSx's? Why don't other companies use the "gearing advantage" that GM does and get even better gas mileage? Why don't they make a lighter, smaller, more powerful engine?

Nice copy/paste. But don't both trying to tell me the advantages of OHC vs pushrod, I know them already.


So this begs the question, why haven't they? Wait... Why hasn't ANY manufacture done this?
Since I know you can't answer this, I will for you. Its BS.
If GM were to produce a DOHC engine that made 405hp again it would be either: Heavier, physically larger, or more expensive than the LSx, or most likely all of the above.
FERRARI, with its high budget builds has not built a powerful DOHC V8 engine that is under 390lbs like the LS2, or LS3. (The 4.3L in the F430 weighs 416lbs).


But be bigger, weigh more, and cost more.
Power per displacement is not efficiency, that's idiocy. Power to weight is efficiency and power to physical size is efficiency because those are actual real world relevant things to performance. In what way would decreasing the displacement of an engine and extracting the same power out of it as before be beneficial in any way?

If GM is making over 400hp/400ft.lbs of torque from an engine that weighs less than 400lbs, and costs around $5,000 why the hell would you bother trying to make a DOHC engine if all you want is 400hp? TRULLY what REAL WORLD benefits would you see if you wanted to make <500hp production engine for a performance car?
If DOHC engines can supposedly get such better gas mileage, then why don't they beat out the LSx's? Why don't other companies use the "gearing advantage" that GM does and get even better gas mileage? Why don't they make a lighter, smaller, more powerful engine?

Simple it cost to damn much and just isn't worth it as GM has proved. No one in their right mind will pay more for a heavier, less gas mileage getting slower car.
Well at least in my world

Nice copy/paste. But don't bother trying to tell me the advantages of OHC vs pushrod, I know them already.


So this begs the question, why haven't they? Wait... Why hasn't ANY manufacture done this?
Since I know you can't answer this, I will for you. Its BS.
If GM were to produce a DOHC engine that made 405hp again it would be either: Heavier, physically larger, or more expensive than the LSx, or most likely all of the above.
FERRARI, with its high budget builds has not built a powerful DOHC V8 engine that is under 390lbs like the LS2, or LS3. (The 4.3L in the F430 weighs 416lbs).


But be bigger, weigh more, and cost more.
Power per displacement is not efficiency, that's idiocy. Power to weight is efficiency and power to physical size is efficiency because those are actual real world relevant things to performance. In what way would decreasing the displacement of an engine and extracting the same power out of it as before be beneficial in any way?

If GM is making over 400hp/400ft.lbs of torque from an engine that weighs less than 400lbs, and costs around $5,000 why the hell would you bother trying to make a DOHC engine if all you want is 400hp? TRULLY what REAL WORLD benefits would you see if you wanted to make <500hp production engine for a performance car?
If DOHC engines can supposedly get such better gas mileage, then why don't they beat out the LSx's? Why don't other companies use the "gearing advantage" that GM does and get even better gas mileage? Why don't they make a lighter, smaller, more powerful engine?

"Most of the engines used in hi-performance race cars and race boats today, are modified from the engines designed for Detroit production automobiles in the 1950s and 60s.

The engines are based on an overhead valve head design with two valves per cylinder, driven by a single camshaft in the block through varied arrangements of tappets and push rods.

Granted, when first introduced, they were a far cry better than Henry Ford’s Flathead engines, that were in Vogue at the time, but not in step with modern day engine technology.

The American Auto Industry, once known for its world leadership, got left behind with the introduction of more efficient, four valve per cylinder, dual overhead cam engines, built in Europe and Japan.The valve train in Schubeck engines, closely relate to those Mercedes and Honda race engines.

Compare the similarities between Schubeck engines and the engines winning at Lemons and Indy. Starting with the valve train, for example, newer engine designs all use overhead cams proven to be less stressful by doing away with problems related to push rods and tappets. Fewer moving parts mean less reciprocating weight. Less weight helps the valve train operate in all rpm ranges with less effort and more efficiency.

Adding to a more relaxed valve train are the smaller and lighter valves and springs, also requiring less spring pressure to operate. Four valves over two valves per cylinder, affords a greater ability for the engine to breath, thereby increasing the volumetric efficiency for more power.

Topping today's list of reasons for performance engine failures, are broker valve train components. All because they are overstressed. Schubeck's solution to this problem is obvious and simple. Reduce the stress."

http://www.schubeckracing.com/new2/index.php?module=pagemaster&PAGE_user_op=view_page&PAGE_id=12&MMN_position=52:52

Simple it cost to damn much and just isn't worth it as GM has proved. No one in their right mind will pay more for a heavier, less gas mileage getting slower car.
Well at least in my world

Why do you say this and they converted to DOHC in the Caddy? LT5 proved you wrong

Simple it cost to damn much and just isn't worth it as GM has proved. No one in their right mind will pay more for a heavier, less gas mileage getting slower car.
Well at least in my world

The LT5 is only 39lbs heavier than the L98. Not a huge difference.

The LT5 was poop anyone who denies it is well in denial and no one still wants to work on it.
Yeah the Northstar is alright, but doesn't get the mileage, power or price advantage of an LSX based motor.

The LT5 is only 39lbs heavier than the L98. Not a huge difference.
Still heavier.

The LT5 was poop anyone who denies it is well in denial and no one still wants to work on it.
Yeah the Northstar is alright, but doesn't get the mileage, power or price advantage of an LSX based motor.

Its not the motor that's efficient for the 10th time. Its the gearing of 1:1 in 4th, making 5th and 6th overdrives.

Still heavier.

Not for the 106hp and 60lbft of torque it makes over the same displacement lt1/4 ls1 and L98

So JDM wasn't telling the twoof:eyes: What happened to the significant weight advantage?

The L98 (along with the LT1) are iron blocks, iron crank, heavy engines. The LT5 is an all aluminum engine.
The difference between an iron block LS1 and an al. one is 93lbs, and from what I understand its an even greater difference with the traditional SBC's like the LT1.
So yes, DOHC = large weight gain and 25psi = fail again.

http://www.schubeckracing.com/new2/index.php?module=pagemaster&PAGE_user_op=view_page&PAGE_id=12&MMN_position=52:52

This doesn't answer anything.

Why do you say this and they converted to DOHC in the Caddy? LT5 proved you wrong

Already explained:
http://www.caranddriver.com/features/columns/c_d_staff/larry_webster/the_pushrod_engine_finally_gets_its_due_column
Marketing.

The L98 (along with the LT1) are iron blocks, iron crank, heavy engines. The LT5 is an all aluminum engine.
The difference between an iron block LS1 and an al. one is 93lbs, and from what I understand its an even greater difference with the traditional SBC's like the LT1.
So yes, DOHC = large weight gain and 25psi = fail again.

Which one offers more performance? Which one is faster? Which one makes more hp/torque? Given the same displacement, once again DOHC wins.


Toodles,

It'll also be easier to negate the weight of 93lbs through the chassis, than gain the 105hp and 60ftlb of torque its missing.

Answer me this then? Why does the Current LSA Pushrod powered CTS-V out run the
M5?
Hint isn't because it has OHC. I'm just saying.

Answer me this then? Why does the Current LSA Pushrod powered CTS-V out run the
M5?
Hint isn't because it has OHC. I'm just saying.

Maybe because it has a blower.

Which one offers more performance? Which one is faster? Which one makes more hp/torque? Given the same displacement, once again DOHC wins.


Toodles,

The LS6 is faster, makes same power, more torque, is lighter, cheaper and smaller. OHV > OHC.
You are embarrassing yourself now.

The LS6 is faster, makes same power, more torque, is lighter, cheaper and smaller. OHV > OHC.
You are embarrassing yourself now.

You're comparing an 18yr old car to an LS6 lol. Nice comparo.

Already explained:
http://www.caranddriver.com/features/columns/c_d_staff/larry_webster/the_pushrod_engine_finally_gets_its_due_column
Marketing.

Dude that guy is smart and that article says it all!

You're comparing an 18yr old car to an LS6 lol. Nice comparo.

And you are comparing a $2,000 engine (L89) to a $20,000 engine (LT5).
Seriously almost none of your arguments are legit, and most are completely illogical and false.
Recapping: The LT5 added well over 100lbs of bulk to the LT1. The LT5 didn't get any better gas mileage. The LT5 almost doubled the cost of the C4. While it was a good engine to mod, and supposedly bulletproof, it is inferior to the LSx engines of today for a good production sports car.

And you are comparing a $2,000 engine (L89) to a $20,000 engine (LT5).
Seriously almost none of your arguments are legit, and most are completely illogical and false.
Recapping: The LT5 added well over 100lbs of bulk to the LT1. The LT5 didn't get any better gas mileage. The LT5 almost doubled the cost of the C4. While it was a good engine to mod, and supposedly bulletproof, it is inferior to the LSx engines of today for a good production sports car.

Show me a link to the cost of an LT5? Secondly, where the trans the same in the LT5 and LT1/4

That's more the construction of the LTx motors to the LSx motors. The LSx motors as a whole are better. Much of the weight difference between the ZR1 and the regular LT1 Vettes was due to the extra oil pump, the bigger wheels/tires, and the 3" wider rear bodywork. And again, we're comparing today's engines to a motor that was designed more than 20 years ago.

Show me a link to the cost of an LT5? Secondly, where the trans the same in the LT5 and LT1/4

LT5s were ~$20k. Designed by Lotus, built by Mercury Marine. And yes, they used the same ZF 6spd transmission.

Show me a link to the cost of an LT5? Secondly, where the trans the same in the LT5 and LT1/4

Good read:
http://www.corvetteactioncenter.com/forums/zr-1-general-technical-discussion/14104-demise-lt5-engine.html

Show me a link to the cost of an LT5? Secondly, where the trans the same in the LT5 and LT1/4

Price was one of the main factors of its demise --the ZR-1 option virtually doubled the price of the basic Corvette. Moreover, the unique styling of the 1990's rear exterior lost some of its exclusivity when extended to all 1991 models and beyond. In addition, the introduction of the improved, small block LT1 engine gave Corvette enthusiasts the muscle they sought, but in the lower-costing basic models.
6,939 ZR-1s were built at a sticker price add-on of $31,258

http://www.zr1netregistry.com/ZR1_about.htm

But be bigger, weigh more, and cost more.
Power per displacement is not efficiency, that's idiocy. Power to weight is efficiency and power to physical size is efficiency because those are actual real world relevant things to performance. In what way would decreasing the displacement of an engine and extracting the same power out of it as before be beneficial in any way?

If GM is making over 400hp/400ft.lbs of torque from an engine that weighs less than 400lbs, and costs around $5,000 why the hell would you bother trying to make a DOHC engine if all you want is 400hp? TRULLY what REAL WORLD benefits would you see if you wanted to make <500hp production engine for a performance car?
If DOHC engines can supposedly get such better gas mileage, then why don't they beat out the LSx's? Why don't other companies use the "gearing advantage" that GM does and get even better gas mileage? Why don't they make a lighter, smaller, more powerful engine?Excellent, excellent points. :thumb:

While only indirectly related to this discussion, please allow me to point out that NO OTHER manufacturer, import or domestic, has been able to bring a performance car to market that could do ALL (ie: power/acceleration/top speed, handling/braking, build quality, comfort/interior space, styling and FUEL ECONOMY) that a base model Corvette can do for anywhere even remotely close to the same price. None.
Cutting edge/high tech? :lol: With all of that world renowned German and/or Japanese engineering and marketing skill, no one else even comes close. :usa: :D :thumb:

And yes, they used the same ZF 6spd transmission.I do believe that all ZR1s (and later L98s) had the ZF but I'd thought there was some point during LT1/LT4 production that the T-56 took over for the ZF?

As far as I know, all C4 6spds were ZF transmissions. And the Corvette has hands-down been the "for the money" king since the C5 was released. And the C6 has actually brought the interior/build quality to levels that can be considered competitive with the best. But you also have to realize that to people who want (and can afford) the best, regardless of price, there are still some things left to be desired. I'm a Corvette guy through and through, but I can still see faults. And thus, areas for improvement.

http://www.zr1netregistry.com/ZR1_about.htm

Where does it say the motor was 20k? For a car that cost 31k, I highly doubt the motor alone would cost that much

OHC can be a more efficient design, but like with everything it has its ups and downs. OHC engines make much higher hp numbers per litre compared to older engines. The downsides being cost, size, weight. The v6 market is going mostly ohc due to the fact that even with the increase in size, its usually not as big of an issue due to it still being smaller than a v8. It does make more power than older pushrod v6s. In retrospect, its trade off for gaining weight is worth the gained efficiency and power.

As for ohv v8 vs ohc v8, the same hurtles apply but now you have even greater increased mass, weight, and therefore costs by going ohc. On average, the hp/L might be higher on ohc engines, but you can have higher displacement, smaller, cheaper engines make the same power. That = higher hp/$.

The reason lsx based engines DO tend to be more efficient mileage wise is they were designed around fuel injection, and to move high amounts of air with little restriction. Compare intake runner sizes from a gen1 sbc to a gen3.

Overall, it creates 2 completely different directions you can go to make power. Each has its flaws, and pros. Mod vs LS, Mod has the advantage of going to a 4 valve setup, which is not cost effective for a ohv setup. LS has the advantage of either going higher displacement base, or changing a single cam to increase air flow.

In the end, theres no v8 that has completely over shrouded the competition (although I do like to think ls style engines overpowered the competition for quite some time, but I'm baised). The only real upper hand I can think of from one setup to the other is the advantage of a forged rotating assembly

And to a prior comment made by 25psi, as of now theres no planned ohc engine planned for vettes or any performance v8. The Northstar OHC V8 replacement that was in design was cancelled. Before design began on the ls1, it was a great debate whether to go ohc or ohv. The guys that designed the ls1 aren't from the stone age, for the same reasons listed above, they chose to design an ohv engine.

If GM is making over 400hp/400ft.lbs of torque from an engine that weighs less than 400lbs, and costs around $5,000 why the hell would you bother trying to make a DOHC engine if all you want is 400hp? TRULLY what REAL WORLD benefits would you see if you wanted to make <500hp production engine for a performance car?
If DOHC engines can supposedly get such better gas mileage, then why don't they beat out the LSx's? Why don't other companies use the "gearing advantage" that GM does and get even better gas mileage? Why don't they make a lighter, smaller, more powerful engine?

1+ Good post.

Take the ZR-1 for instance. GM produced a 90's exotic 400hp dohc LT5 motor that revolutionized GM's v8 heritage. They named it king of the hill for a reason. But the downfall of the dohc LT5 was the pricetag. Im guessing the GM was going to take the dohc route for the future of SBC, but looked at the ridiculous cost and said no way. Then came the pushrod LS series. The LS series are very cheap, very simple, and very efficient for a world leader v8. The LS series will replace the sbc v8 as the world's greatest v8 engine because of those factors.

Ford's picked the ohc/dohc v8 route with success. They produce v8 line that virtually all parts are interchangeable, I believe thats where the word modular comes from. They sell thousands of fleet v8 cars and trucks to government bodies. Also, engineered a arguably strong ohc/dohc motor. All of those factors keep cost down.

GM and Ford are truly deeply in love money and would rather keep it in their pocket. Both use new technologies to produce engines that are competitively efficient and competitively priced. The LS and Mod motors are winners in that category.


GM and Ford are long time best friends and worst enemies. They brutally compete for sales and bash each other in the media on the weekdays. Then, they race/compete their cars on the weekends for bragging rights not for a quarterly profit. However, Ford needed to bolt on a supercharger to their Modular engines to compete and sometimes beat the LS series for racing bragging rights. GM did the same with the lsa and ls9 and gave the middle finger to Ford. Boost is the future and GM was late to the game. :devil:

1+ Good post.

Take the ZR-1 for instance. GM produced a 90's exotic 400hp dohc LT5 motor that revolutionized GM's v8 heritage. They named it king of the hill for a reason. But the downfall of the dohc LT5 was the pricetag. Im guessing the GM was going to take the dohc route for the future of SBC, but looked at the ridiculous cost and said no way. Then came the pushrod LS series. The LS series are very cheap, very simple, and very efficient for a world leader v8. The LS series will replace the sbc v8 as the world's greatest v8 engine because of those factors.

Ford's picked the ohc/dohc v8 route with success. They produce v8 line that virtually all parts are interchangeable, I believe thats where the word modular comes from. They sell thousands of fleet v8 cars and trucks to government bodies. Also, engineered a arguably strong ohc/dohc motor. All of those factors keep cost down.

GM and Ford are truly deeply in love money and would rather keep it in their pocket. Both use new technologies to produce engines that are competitively efficient and competitively priced. The LS and Mod motors are winners in that category.


GM and Ford are long time best friends and worst enemies. They brutally compete for sales and bash each other in the media on the weekdays. Then, they race/compete their cars on the weekends for bragging rights not for a quarterly profit. However, Ford needed to bolt on a supercharger to their Modular engines to compete and sometimes beat the LS series for racing bragging rights. GM did the same with the lsa and ls9 and gave the middle finger to Ford. Boost is the future and GM was late to the game. :devil:

I agree with your whole post EXCEPT that last part. Mach 1 ring a bell? And I'd wager that (comparing engines) the GT500/'03-'04 Cobra engine is just as strong/easy to modify, if not moreso, than the LSA and the LS9. So I wouldn't exactly call that "gave the middle finger to." And before the "Corvettes are better than Mustangs" shit starts flying, I am comparing motors only, not cars.

I agree with your whole post EXCEPT that last part. Mach 1 ring a bell? And I'd wager that (comparing engines) the GT500/'03-'04 Cobra engine is just as strong/easy to modify, if not moreso, than the LSA and the LS9. So I wouldn't exactly call that "gave the middle finger to." And before the "Corvettes are better than Mustangs" shit starts flying, I am comparing motors only, not cars.

This is the exact response that makes the the rivalry between Ford and GM simply bad ass.

I was only talking about motors too. The Mustang and Vette are to completely different animals. The Mustang is a profit maker, the Vette is a race car champion. It is so easy to make power with boost. Ford just got an early start and GM just now caught on.

Where does it say the motor was 20k? For a car that cost 31k, I highly doubt the motor alone would cost that much

You need to read more carefully:
"The price of the basic coupe was $31,979, but with the addition of the ZR-1's special performance package listed at $27,016, the car was not meant for the faint-hearted or bargain-conscious. It's reported that some dealers asked and were paid $100,000 for the then ultimate in American sports cars. "

"2,044 ZR-1s were built at a sticker price add-on of $31,683" etc. etc.

The 1990 Zr1 PACKAGE was a $31,000 package over the base coupe. So in other words the 1990 ZR1 brand new cost $58,995.

And if you would kindly read the link I posted earlier you would see:
"And, given an estimated $25,000 price premium for the LT5 engine, the cost of this small increment of power is astronomical."

You need to read more carefully:
"The price of the basic coupe was $31,979, but with the addition of the ZR-1's special performance package listed at $27,016, the car was not meant for the faint-hearted or bargain-conscious. It's reported that some dealers asked and were paid $100,000 for the then ultimate in American sports cars. "

"2,044 ZR-1s were built at a sticker price add-on of $31,683" etc. etc.

The 1990 Zr1 PACKAGE was a $31,000 package over the base coupe. So in other words the 1990 ZR1 brand new cost $58,995.

And if you would kindly read the link I posted earlier you would see:
"And, given an estimated $25,000 price premium for the LT5 engine, the cost of this small increment of power is astronomical."

I stand corrected

Recapping: The LT5 added well over 100lbs of bulk to the LT1.Not only that but the ZR1 as a whole also weighed almost 200 pounds more overall than the base LT1. Some (most) of it was due to the motor and I'll assume that some was due to some heavier duty supporting pieces to accept the more potent (and again, physically heavier/larger) motor as well as more standard content and larger rear wheels/tires.
Still an awesome performer though and capable of solid 12 second passes which was not at all common back in 1990. :thumb:

Not only that but the ZR1 as a whole also weighed almost 200 pounds more overall than the base LT1. Some (most) of it was due to the motor and I'll assume that some was due to some heavier duty supporting pieces to accept the more potent (and again, physically heavier/larger) motor as well as more standard content and larger rear wheels/tires.
Still an awesome performer though and capable of solid 12 second passes which was not at all common back in 1990. :thumb:

The weight of the current ZR1(supercharger, water to air intercooler, etc..) would be the same as if they put a 7.0 liter DOHC VVTI setup. And I bet, the 7 liter dohc would produce more power as well.

The weight of the current ZR1(supercharger, water to air intercooler, etc..) would be the same as if they put a 7.0 liter DOHC VVTI setup.You may be correct on that. :nod:





And I bet, the 7 liter dohc would produce more power as well.You may not be correct on that one. ;)

You may be correct on that. :nod:





You may not be correct on that one. ;)

lol. Going by what other manufactures are producing with 3.5-3.8 liters:

350z 3.7 liter--334hp
Porsche 3.6--- 415

Theoretically, you should be able to produce in excess of 650hp n/a. The LT5 produces 105hp and 60lbft of torque more than the Lt1/4 and ls1 with the same displacement. And with todays technology(vvti) you should be able to with ease

The higher the horsepower, the harder the gains. Theoretcally, maybe that would work. In actuality, I'm doubtful. Otherwise viper engines especially would be making much greater power. I'd bet it'd be in the 500's whoever is making this 7L DOHC vvti. Still, potent for a N/A engine (probably making more than an ls7@7.0Ls) but again even if the manage to overcome the weight issue, how cost effective is it?

The higher the horsepower, the harder the gains. Theoretcally, maybe that would work. In actuality, I'm doubtful. Otherwise viper engines especially would be making much greater power. I'd bet it'd be in the 500's whoever is making this 7L DOHC vvti. Still, potent for a N/A engine (probably making more than an ls7@7.0Ls) but again even if the manage to overcome the weight issue, how cost effective is it?

The reason why it's harder is because of the limit VE you're able to obtain with a pushrod motor. Being that the Viper does not have DOHC or 4 valves per cylinder, makes it harder to increase hp without increasing displacement.

M5 5.0 liter=500hp
Porsche 3.6 liter=416hp
350z 3.7 liter=334hp
LS-F(Lexus) 4.4 liter = 416hp


As I stated earlier, the LT5 made 106hp and 60lbft of torque more than the LT1/4 and while having the same displacement. It should be no problem for a DOHC 7.0 liter to make in upwards of 650-700hp n/a.

Cost I don't think should be a problem considering you're paying 105-120k for a ZR1 and 75k for a C6Z. Depending on the supply and demand, this will determine the price. Remember GM converted to DOHC in the new 6cyl Caddies and price is relatively the same as previous models.

The weight of the current ZR1(supercharger, water to air intercooler, etc..) would be the same as if they put a 7.0 liter DOHC VVTI setup. And I bet, the 7 liter dohc would produce more power as well.

It wouldn't produce any more power because GM only wanted 630hp. Do you honestly think they squeezed everything out of the LS9? If so you really are living in a fantasy land.

It wouldn't produce any more power because GM only wanted 630hp. Do you honestly think they squeezed everything out of the LS9? If so you really are living in a fantasy land.

I'm talking about n/a vs n/a. Without the supercharger, the LS9 wouldn't make anywhere close to what a 7.0 liter dohc motor would make(c6z vs Dohc comparison). The Viper motor, although impressive, does not make the power it should with such as huge motor. Why do companies make dohc conversion for the lsx motors?

I'm talking about n/a vs n/a. Without the supercharger, the LS9 wouldn't make anywhere close to what a 7.0 liter dohc motor would make(c6z vs Dohc comparison). The Viper motor, although impressive, does not make the power it should with such as huge motor. Why do companies make dohc conversion for the lsx motors?

What makes you think it wouldnt be anywhere close? DOHC isnt the be all end all of motors....its merely another option. A more costly heavier option at that. Will it make more power...probably but not insane amounts.

Your talking about fantasy land with shit that doesnt matter in the first place.


The real question is why dont more companies make DOHC conversions?

Because its a fucking waste of money.

What makes you think it wouldnt be anywhere close? DOHC isnt the be all end all of motors....its merely another option. A more costly heavier option at that. Will it make more power...probably but not insane amounts.

Your talking about fantasy land with shit that doesnt matter in the first place.


The real question is why dont more companies make DOHC conversions?

Because its a fucking waste of money.

Because every example that I've should you, indicates that it will. And people keep speculating that it will cost more with no physical proof. GM switched from pushrod to DOHC in the V6 Caddy and the cost are relatively the same as previous models. If you have the supply and demand the benefits far out weigh the negative.

So your telling me that the LT5 did not make a considerable amount more power and torque than the 5.7 in the LT1/4? LOL! What do you consider 106hp and 60lbft of torque more from the same displacement?

The conversion to make dohc motors from pushrod would be expensive, just as if it where visa versa.

Like I said, no shit there will be a difference. But your being an idiot by comparing a mass produced motor.

A the lt5 had a different bore and stroke, higher compression ratio, hand built using mostly race parts, better flowing heads and DOHC. Not just a DOHC lt1.

No shit it made that much more hp....its a fucking racing engine. Again you jump to irrelevent things to try and make a point.

Since you want to play stupid, how much more would it cost me to buy an lt5 over a lt1? Which is cheaper to mod????Fix???


Thanks for playing.

Like I said, no shit there will be a difference. But your being an idiot by comparing a mass produced motor.

A the lt5 had a different bore and stroke, higher compression ratio, hand built using mostly race parts, better flowing heads and DOHC. Not just a DOHC lt1.

No shit it made that much more hp....its a fucking racing engine. Again you jump to irrelevent things to try and make a point.

Since you want to play stupid, how much more would it cost me to buy an lt5 over a lt1? Which is cheaper to mod????Fix???


Thanks for playing.

Is cheaper always better? Secondly, as you clearly stated, the LT1 was a massed produced motor. So the cost of performance parts would of course be cheaper. Supply and Demand.

It wasn't until 12 years later that the LS6 benefited from a higher-lift camshaft and higher-compression pistons to raise horsepower from 350 to 405, and torque from 340 lb.-ft. to 400 lb.-ft.

Toodles,

Is cheaper always better? Secondly, as you clearly stated, the LT1 was a massed produced motor. So the cost of performance parts would of course be cheaper. Supply and Demand.

It wasn't until 12 years later that the LS6 benefited from a higher-lift camshaft and higher-compression pistons to raise horsepower from 350 to 405, and torque from 340 lb.-ft. to 400 lb.-ft.

Toodles,

So you just told me nothing I didnt already know there. I gave you many reasons why the lt5 made more hp then a lt1. I never said that dohc doesnt make more power than a pushrod motor, its just not the greatest thing ever. You just like it because your an import nutswinger and thats pretty much all they use.


Toodles??????? Are you some old english cunt?

Like I said, no shit there will be a difference. But your being an idiot by comparing a mass produced motor.

A the lt5 had a different bore and stroke, higher compression ratio, hand built using mostly race parts, better flowing heads and DOHC. Not just a DOHC lt1.

No shit it made that much more hp....its a fucking racing engine. Again you jump to irrelevent things to try and make a point.

Since you want to play stupid, how much more would it cost me to buy an lt5 over a lt1? Which is cheaper to mod????Fix???


Thanks for playing.

"Most of the engines used in hi-performance race cars and race boats today, are modified from the engines designed for Detroit production automobiles in the 1950s and 60s.

The engines are based on an overhead valve head design with two valves per cylinder, driven by a single camshaft in the block through varied arrangements of tappets and push rods.

Granted, when first introduced, they were a far cry better than Henry Ford’s Flathead engines, that were in Vogue at the time, but not in step with modern day engine technology.

The American Auto Industry, once known for its world leadership, got left behind with the introduction of more efficient, four valve per cylinder, dual overhead cam engines, built in Europe and Japan.The valve train in Schubeck engines, closely relate to those Mercedes and Honda race engines.

Compare the similarities between Schubeck engines and the engines winning at Lemons and Indy. Starting with the valve train, for example, newer engine designs all use overhead cams proven to be less stressful by doing away with problems related to push rods and tappets. Fewer moving parts mean less reciprocating weight. Less weight helps the valve train operate in all rpm ranges with less effort and more efficiency.

Adding to a more relaxed valve train are the smaller and lighter valves and springs, also requiring less spring pressure to operate. Four valves over two valves per cylinder, affords a greater ability for the engine to breath, thereby increasing the volumetric efficiency for more power.

Topping today's list of reasons for performance engine failures, are broker valve train components. All because they are overstressed. Schubeck's solution to this problem is obvious and simple. Reduce the stress."

This is coming from a well known racing program that also used Pushrod Motors:

http://www.schubeckracing.com/new2/index.php?module=pagemaster&PAGE_user_op=view_page&PAGE_id=12&MMN_position=52:52

So you just told me nothing I didnt already know there. I gave you many reasons why the lt5 made more hp then a lt1. I never said that dohc doesnt make more power than a pushrod motor, its just not the greatest thing ever. You just like it because your an import nutswinger and thats pretty much all they use.


Toodles??????? Are you some old english cunt?

Caddy uses DOHC, that makes me an import nutswinger :eyes:

Toodles,

"Topping today's list of reasons for performance engine failures, are broker valve train components. All because they are overstressed. Schubeck's solution to this problem is obvious and simple. Reduce the stress"


Like those Tundra camshafts breaking?

You can post all the links you want. Yes the engine breaths easier with dohc. i dont know how many times you like to hear it.

But the other end of the spectrum to your stupid racing post is that top fuelers and such all use pushrod motors.

Keep tooting your own horn though.

"Topping today's list of reasons for performance engine failures, are broker valve train components. All because they are overstressed. Schubeck's solution to this problem is obvious and simple. Reduce the stress"


Like those Tundra camshafts breaking?

You can post all the links you want. Yes the engine breaths easier with dohc. i dont know how many times you like to hear it.

But the other end of the spectrum to your stupid racing post is that top fuelers and such all use pushrod motors.

Keep tooting your own horn though.


13 camshaft broken out of 200k in the first year is less than the roofs that came off the Z06. I suggest you do a search, before bringing to light statistics you know nothing about.


Toodles,

Caddy uses DOHC, that makes me an import nutswinger :eyes:

Toodles,

Your an import nut swinger regardless of what caddy uses. You know it, get over it, life goes on. I never said there was anything wrong with DOHC. Good Im glad Caddy uses it. God you fucking act like you invented mother fuckin DOHC.


Plus you sound like a faggot when you say Toodles.

13 camshaft broken out of 200k in the first year is less than the roofs that came off the Z06. I suggest you do a search, before bringing to light statistics you know nothing about.


Toodles,



How many camshaft did chevy break.......in stock applications ever? WTF does roofs have to do with doch.

Attacking randomly again at domestics. You cant hide it.

Its okay to swing from the nippon nuts:swing:

"Topping today's list of reasons for performance engine failures, are broker valve train components. All because they are overstressed. Schubeck's solution to this problem is obvious and simple. Reduce the stress"


Like those Tundra camshafts breaking?

You can post all the links you want. Yes the engine breaths easier with dohc. i dont know how many times you like to hear it.

But the other end of the spectrum to your stupid racing post is that top fuelers and such all use pushrod motors.

Keep tooting your own horn though.

Find me someone that is using nitro methane push rod top fuel motor on the street lol. Nice comparo :eyes:! The reason why they are able to produce that much power is Nitro Methane.

Like many other motor sport formulas originating in the United States, the NHRA favors heavy restrictions on engine configuration, rather than technological development. This restricts the teams to using many decades old technologies.

The engine used to power a Top Fuel drag racing car has its roots in the second generation Chrysler Hemi 426 "Elephant Engine" made 1964-71. Although the Top Fuel engine is built exclusively of aftermarket parts, it retains the basic configuration with two valves per cylinder activated by pushrods from a centrally-placed camshaft. The engine has hemispherical combustion chambers, a 90 degree V angle; 4.8" bore pitch and a 5.4" cam lift. The configuration is identical to the overhead valve, single camshaft-in-block "Hemi" V-8 engine which became available for sale to the public in selected Chrysler Corporation (Dodge, DeSoto, and Chrysler) automotive products in 1952.

The NHRA competition rules limit the displacement to 500 cubic inch (8194 cc). A 4.19" (106.4 mm) bore with a 4.5" (114.3 mm) stroke are customary dimensions. Larger bores have been shown to weaken the cylinder block. Compression ratio is about 6.5:1, as is common on engines with overdriven (the supercharger is driven faster than the crankshaft speed) supercharger

How many camshaft did chevy break.......in stock applications ever? WTF does roofs have to do with doch.

Attacking randomly again at domestics. You cant hide it.

Its okay to swing from the nippon nuts:swing:

How many rocker arms, engine failures and trans issues in the C6Z. I suggest you go over to the Corvetteforum and check em out.

Just for the record My engine blew while on track at a performance driving school and our friends at GM WILL NOT WARRANTY THE ENGINE REPLACEMENT. The warranty language states that they will not cover damage caused while racing or competetive driving. I was not involved in either situation. I was enrolled in a performance driving school that does not teach racing or allow any competition between students. GM refused to review my class enrollment documents, would not inspect my engine or go through its computer info to even find out why or what caused the engine failed. Many dealers told me that I would have been better off if I had lied add told them it happened on the highway. DO NOT TELL GM YOU WERE EVER ON A TRACK! good luck to all others that enjoy track time with their Z's. I understand that they are changing the dry sump to a larger capacity tank for the 09's. Im now considering a Lingenfelter built engine for my GM BLACKBALLED Z06.

GM came out with a service bulletin specifically covering the ZR1, but what is interesting is how they work it in with what they claim is existing GM policy:

"General Motors designed and produced the ZR1 be driven on the roads. While the car is capable of awesome displays of power and speed it was not designed to be "raced". All of the restrictions that are currently in place for all of GM’s products are in place on the ZR1 as well. There are several notations in the warranty booklets that explain that GM may deny warranty coverage if the vehicle or part has failed due to abuse, neglect, improper or insufficient maintenance or modifications not approved by GM. This includes common "upgrades" customers may make such as wheels, tires, suspension, brakes, air induction and engine calibrations. Please ensure this is covered with the owner when the vehicle is delivered. The ZR1 will perform well in a track environment; however, it was not designed, built or sold as a "track car." If an owner elects to use the car in such a manner, it is outside the intent of the warranty as supplied by General Motors and any damage as a result may not be covered by the GM warranty. Explaining this to a customer before the car is sold may prevent misunderstandings later."

In any event, how they can know that the blown engine was "a result" of an arguable racing activity is difficult to fathom if they haven't taken the engine apart to see why it failed.

Take that nonsense somewhere rookie. Every car manufacture has issues. It's not an isolated case amongst imports as you're making it to be.

The discussion we where having before you arrived was informational. You turned this into a pissing contest with your subconscious hatred toward imports.


Toodles,

Your an import nut swinger regardless of what caddy uses. You know it, get over it, life goes on. I never said there was anything wrong with DOHC. Good Im glad Caddy uses it. God you fucking act like you invented mother fuckin DOHC.


Plus you sound like a faggot when you say Toodles.

I don't want to embarrass you by telling you what I own. So I'll save you the trouble.

Chao,

I'm talking about n/a vs n/a. Without the supercharger, the LS9 wouldn't make anywhere close to what a 7.0 liter dohc motor would make(c6z vs Dohc comparison).

Wrong again cheif, and this is the last time I'll say it. GM CHOSE to make 630hp. A DOHC while having the potential to make that much power or more, would not make any more magically.


The Viper motor, although impressive, does not make the power it should with such as huge motor.

Hello, this is reality and logic speaking, are you there 25psi? Dodge isn't anywhere NEAR the potential of that engine, they again CHOSE to make 600hp with that engine.


Why do companies make dohc conversion for the lsx motors?
Why did they stop making the conversion?

Because every example that I've should you, indicates that it will.

Every example indicates it will be more expensive, heavier, and physically bigger. Every example you have shown has had an LSx engine swapped in the place of that DOHC engine.


And people keep speculating that it will cost more with no physical proof. GM switched from pushrod to DOHC in the V6 Caddy and the cost are relatively the same as previous models. If you have the supply and demand the benefits far out weigh the negative.
http://www.corvetteactioncenter.com/forums/zr-1-general-technical-discussion/14104-demise-lt5-engine.html


It wasn't until 12 years later that the LS6 benefited from a higher-lift camshaft and higher-compression pistons to raise horsepower from 350 to 405, and torque from 340 lb.-ft. to 400 lb.-ft.

Toodles,
Again, do you honestly think GM just suddenly discovered that if they put in a bigger cam with better flowing heads they would gain power? You really are dense... GM ONLY WANTED TO MAKE 345hp!
Now unless you have some logical arguments that you can provide SOLID proof of please GTFO because with each post you are looking more and more like a child.

To the one who thinks hes not an import nut swinger. I went through the first 3....just the first 3 pages of threads you started and out of 75.....43 of them were about imports or import vs domestic racing or import vs import vs domestic racing.

Get over it, your a nutswinger.

To the one who thinks hes not an import nut swinger. I went through the first 3....just the first 3 pages of threads you started and out of 75.....43 of them were about imports or import vs domestic racing or import vs import vs domestic racing.

Get over it, your a nutswinger.

You're a 25psi nutswinger, so we're even

You're a 25psi nutswinger, so we're even

In order to swing from your nuts, I would have to like you.

NHRA motors make a shitload of power, yes its nitromethane but dohc motors would not work in this application

my comment was dumb. I was drunk and thinking the viper was dohc...

I think the general statement being made by 25psi and what most are overlooking is the fact that ohc tend to make more hp/L compared to ohv. Not necessarily that the LS based engine isn't efficient for what it is. On AVERAGE, OHC gets you higher hp/L, where OHV gets you higher HP/$, HP/.lb, and less over size. Its one compromise for the other.

my comment was dumb. I was drunk and thinking the viper was dohc...

I think the general statement being made by 25psi and what most are overlooking is the fact that ohc tend to make more hp/L compared to ohv. Not necessarily that the LS based engine isn't efficient for what it is. On AVERAGE, OHC gets you higher hp/L, where OHV gets you higher HP/$, HP/.lb, and less over size. Its one compromise for the other.

Thank you. I never said that the lsx based engine was not efficient at making power, but that on a parallel comparison it won't make the same as a dohc setup.

nobody was arguing that dohc wont make more power, 25psi just seems to think it will make tons more power.

try fitting a 7.0l doch motor in anything and you'll know why gm uses pushrods. its lighter, more compact. it may make less hp/liter from the factory but it kicks the shit out of doch in the horsepower/engine weight horsepower/engine size. those are 2 things i care about. not horsepower/liter. thats magazine marketing bull shit that doesnt mean anything. an engine makes what it makes. plus you have a TON more potential with heads cams on a pushrod. go spend 5 grand to modify a bmw v10 and make 20-30 horsepower over stock. yay....

if i can have a 7l engine thats smaller, lighter, better power and more efficient then a dohc v10 i think ill take it. ohc engines are older then pushod designs. just two different ways to make power.

sorry to interupt this argument but this list is shit!!!! i hate to admit it but the 3.6 should not be on there. i work at a cadillac dealer and see that those are the absolute bigges piles around. they have huge timing chain problems and its rare the chains make it past 60,00 more often then though they end up with new chains as new as 20,000!!!!. ive also herd nothing but bad things about the hemi. i hear they spin bearings like it there jobs. what does deserve recongnition is the ls motors. my dealer is also a gmc dealer and all the trucks that come in its rare they have any motor problems. the only thing close to a motor problem they ever have is that sometimes the rear studs on the exhaust manafolds break. thats it!!!

I remember looking at older list of the top ten. It quoted that the ls designed motors where to old an need updated, Thats why i don't really care who makes there top motor list anymore