Generation IV Internal Engine - 4-Valves Per Cylinder - Why not?

Corvette used to have this, too bad now. At low lifts they provide much more flow. I am sure many have seen this product - 32-valve head bolt on the LSx (new). They have a line of 32-valve heads. I am interested in opinions (besides, of course, it's expensive) of the product or the company? Hopefully someone will have some direct experience or know of someone why did.

http://www.araoengineering.com/LSX.htm

they are pricey thats for sure

Corvette used to have this, too bad now. At low lifts they provide much more flow. I am sure many have seen this product - 32-valve head bolt on the LSx (new). They have a line of 32-valve heads. I am interested in opinions (besides, of course, it's expensive) of the product or the company? Hopefully someone will have some direct experience or know of someone why did.

http://www.araoengineering.com/LSX.htm

This topic comes up every now and then, and seems to be more prevalent as of late. Four valves per cylinder is great, but the complexity of doing so with a pushrod engine doesn't warrant the potential gains, and doing it with overhead cams adds a lot of size and weight to the engine (and that keeps the center of gravity high - big no no for performance). Take a look at an '03-'04 Cobra engine bay...that engine is MASSIVE compared to a standard LS1/2/3/7.

Go do some research on pushrod vs. overhead cam engines, and I think you'll be surprised at just how efficient the old design is. Pushrod engines make a ton of average power, but they don't tend to be able to spin as high as an overhead cam design. Then again, you seem to have to spin an overhead cam engine to the moon to get anything useful out of it (unless you put a roots style blower on it like Ford did).

This topic comes up every now and then, and seems to be more prevalent as of late. Four valves per cylinder is great, but the complexity of doing so with a pushrod engine doesn't warrant the potential gains, and doing it with overhead cams adds a lot of size and weight to the engine (and that keeps the center of gravity high - big no no for performance). Take a look at an '03-'04 Cobra engine bay...that engine is MASSIVE compared to a standard LS1/2/3/7.

Go do some research on pushrod vs. overhead cam engines, and I think you'll be surprised at just how efficient the old design is. Pushrod engines make a ton of average power, but they don't tend to be able to spin as high as an overhead cam design. Then again, you seem to have to spin an overhead cam engine to the moon to get anything useful out of it (unless you put a roots style blower on it like Ford did).
Actually the OHC design is older than the pushrod design.

Other than that, I agree with you 110% :cheers:

Actually the OHC design is older than the pushrod design.

Other than that, I agree with you 110% :cheers:

That is true...definitely neglected to mention that one.

I'd be seriously concerned about the needle bearings eating up a substantial amount of load. Same with the lifter and push rod. Just because you have 2 doesn't mean that the seat pressures of the valves and springs are the same or less (which I highly doubt).

Arao gave me a price of $10,000 for complete ready to install six stud heads for the LSX block. Including Jessel rockers and valve covers.



.

he has a horrible reputation. if you want to give money away send it to me instead.

read this thread.

http://www.ls1tech.com/forums/showthread.php?t=694485

You want a head that flows a ton from .300"-.500" and you want to actully reduce flow at .100"-.200" 4 valve heads flow a ton down low so the cam timing gets critical, just ask any Ford Cobra owner who has ever spent $1000 on cams to make 10 HP.

all jokes aside- this argo head might be good or bad-might flow big or down low-but i don't know that-

so my point is how much power do u real want- i am pretty sure with $10,000 spent on any ls1 to et,l92,ls7,all pro heads etc etc is more that enough for anyone-

i highly reckon it comes down to money and 10 k on heads is over the top unless full time racing with a big bank balance-

people and sponsors are building - quote me if i am wrong here people lsx long block's for under 10 or just over 10 k and some are pushing out some insane rwhp hp and torque-

I just could not spend that much on a top end unless it was a all out drag car or i had a sponsor-

but huge credit to argo for thinking out of the box to come up witha head like that -unless someone already done one in the past-

my .2 cents-

You want a head that flows a ton from .300"-.500" and you want to actully reduce flow at .100"-.200" 4 valve heads flow a ton down low so the cam timing gets critical, just ask any Ford Cobra owner who has ever spent $1000 on cams to make 10 HP.

The article on this site discussed "area under the curve" very important. However, I do not get the reduced flow deal with low lift in an LS7 motor. :(

Four-valve heads have their pro's and con's, but putting all of those aside, for $10000 you can build yourself one hell of a two-valve motor. The "bang for the buck" factor of those heads is very poor. If they managed to get the price to around half or a third of that then they might be worth their price tag.

Four-valve heads have their pro's and con's, but putting all of those aside, for $10000 you can build yourself one hell of a two-valve motor. The "bang for the buck" factor of those heads is very poor. If they managed to get the price to around half or a third of that then they might be worth their price tag.


100% with u-

Four-valve heads have their pro's and con's, but putting all of those aside, for $10000 you can build yourself one hell of a two-valve motor. The "bang for the buck" factor of those heads is very poor. If they managed to get the price to around half or a third of that then they might be worth their price tag.

Or go FI.

Or go FI.
cant beat a tt tq band a nd peak at 15+psi on the street :burn:

The article on this site discussed "area under the curve" very important. However, I do not get the reduced flow deal with low lift in an LS7 motor. :(
At low lifts with a big valve(valves) or large curtain area, you run into reversion problems. That is why is considered beneficial at low lift points(.100, .200) to actually flow a little less than what you would consider normal on a smaller valve head.

Actually the OHC design is older than the pushrod design.

Other than that, I agree with you 110% :cheers:
OT: Can you please back that up with proof? If it is then thats one more point I can make in defending the OHV against the ignorant/uninformed masses ;)

The first OHC engines were two or four valve per cylinder designs from companies like Fiat (1912), Peugeot Grand Prix (1913,4 valve), Alfa Romeo GP - (1914, 4 valve), 6C- 1925, Maserati (Tipo 26, 1926) and Bugatti (Type 51, 1931).

Also, the Duesenberg Model J in 1928 had an inline-8 DOHC and made 285HP in unsupercharged form. The SJ in 1932 was supercharged.

OT: Can you please back that up with proof? If it is then thats one more point I can make in defending the OHV against the ignorant/uninformed masses ;)

It is well known that overhead cam engines were among the first that ever appeared.

You want a head that flows a ton from .300"-.500" and you want to actully reduce flow at .100"-.200" 4 valve heads flow a ton down low so the cam timing gets critical, just ask any Ford Cobra owner who has ever spent $1000 on cams to make 10 HP.

I'm not trying to argue with you Brian, but I've seen some pretty good running 4V H/C cobras putting down some very respectible numbers and they seem to run like a bat out of hell.

So are you refering to forced induction 03/04 cobras?

not that this is the reason, but can you imagine how few of us would be running around with mean sounding hard cammin' cars if our cars with DOHC cars?