I am building my first performance small block Chevy and I would appreciate the guidance and input from folks who have gone down this path before me. I have assembled and modified many import motors but other than a stock rebuild I have never wrenched on the Chevy V8.

Project
I will be dropping a 350 block into a 1972 Datsun 240Z. 010 block from 1973.

Why a SBC in a 240Z?
I already have a very high strung 240Z that is 20% street/80% race (bad idle, obnoxiously firm suspension, very grippy racing clutch), so this car is intended to be more streetable. I figured the V8 motor will give me a much smoother powerband than the I6 does when it is built for 250+ HP.

Intended Use
75% street/ 25% road course. Spirited street/canyon driving "for fun" (not a daily driver), non-competitive high performance driving events on road course race tracks.

Power Goals
It would be nice to have 400 HP for bragging rights, but I think if I am anywhere in that area it will feel pretty darn good in a car that weighs 2400 lbs.

Budget
The idea is to show how much power can be put down by the venerable Chevy V8 without spending much money. I can wind the heck out of an L28ET and get 400 HP very reliably... for about $10,000 done right. I believe I can put 400 HP in a SBC that will run all day for under $2000. I already bought the motor, intake, carb and headers listed below for $400.

Planned Build
Edelbrock Performer 750 carb
Edelbrock Performer RPM Intake
ProComp PC3003S Aluminum Heads (64cc/210cc, straight plug)
Custom valvetrain and head work from my machinist
1.6 Roller Rockers (mfg. not selected yet)
Hydraulic roller lifters (mfg. not selected yet)
Hooker Super Comp Block Hugger headers (to clear stock steering in my 240Z)
Whatever hydraulic cam the smart people at COMP recommend with this setup
Stock bottom end w/ stock forged, dished pistons

Discussion
Will this work? I am choosing the cam last as I figure that is what the cam help line is for; they know their products after all.

Will the large runners on the 210cc heads match up with the intake? Any special gaskets I need to think about? Is that too much intake volume for 350 ci?

Any idea what CR this combo will yield? Looking to run California's lousy 91 octane at most; I don't want to have to put race gas in here all the time. 87 wouldn't be bad, either, because I'd love to beat my import buddies using Regular Unleaded.

No need to bash the ProComp heads in this thread. They are dirt cheap and my engine builder has put them in several race cars. Some of those race cars are winners, both in drag and dirt. He likes the 3rd gen ProComp head at the price, and he's willing to do the machine work to make them pretty. He says he refuses to use their assembled heads as he's seen too many assembly issues and doesn't trust their valvetrains. I trust the guy and he's always given me good motors, so...

What else? Will she make power?

Thanks all,
David

 

You are on track, i would do a 383 at least with that set of heads. With 9.7 to 1 compression you can go with mid grade fuel. A comp cam XE288HR would be fine with the cubes and heads and make over 450 HP. With that intake as well, not a bad choice.

 

Thanks very much for taking the time to comment - this is the kind of insight I need.

I have a new development. I managed to find a set of lightly used Edelbrock E-Tec 200 Vortec heads for $500, assembled, complete with roller rockers. Unfortunately, the Vortec heads mean my RPM intake that came with my motor is useless, but if I understand correctly this is a no brainer and the extra expense of a Vortec intake will be well worth it. Perhaps I can even recover a little bit of $ by selling the RPM.

So, I need a new Vortec intake. Given my intended use, should I be looking at an RPM, or an RPM air gap? I will be streeting this so I don't want to give up too much under the curve, but I do want it to pull out to 6500 RPM.

Sound like the right choice? What about the 200cc runners - ZONES89RS, you mentioned that 210cc sounded like too much for a 350. I won't be stroking it, at least not now, so am I still going to be breathless down low, or will the slightly smaller 200cc runners on the E-Tec help me out a little?

 

That is a great set of heads for what you are doing and a good deal if they are sound pieces. But YES, the intake change will be a great decision to use those heads. The RPM air gap is the best well rounded intake money can buy. Not to mention the professional products intake which is a knock off of the edelbrock is just as good. Made in china but is the same, just cheaper. With 10.5 to 1 compression, you will have no issues with supreme fuel and the heads will be supplying the flow you need to make excellent power.

 

Dude, you are awesome.

Thanks for turning me on to the Professional Products intake! I put a feeler out through a friend, and long story short, I may be repping their product on my car.

I just returned home from a few parts pickups in LA and Orange County. Here is my current receipt total for all items in hand:

$200 - 350 block: good compression, running motor.
$ 80 - Edelbrock 750 carb: ~500 miles on it (PO went with a Demon)
Free - Low profile chrome air cleaner assy: Came with carb
$500 - E-Tec 200 Vortec heads: ~3000 miles used, assembled, ported.
Free - Dual valve springs: Came with heads
Free - 1.6 Rocker Rollers: Came with heads
$ 50 - Flat top pistons - used, good condition.
$100 - Hooker Block Hugger 1.75" headers
($0?) - Professional Products Crosswind Vortec intake (as RPM Air Gap)

That puts me at $930 without a cam and lifters. Another $600 goes to my engine builder for assembly, machining, seals, gaskets, rings, pushrods, studs, assembly hardware, etc.

I think I have enough info to start shopping for a cam/lifter package. Recommendations appreciated... I am headed to ISKY now.

 

get a custom ground comp .496/.520 234/244 on a 110

 

Tha is about the cam i recommended(236/242 @.050 and .520/.540 lift on a 110 LSA).

 

one of my all time favorite cams. using them with those 1.6 rockers will give you .555 and .576 lift. just make sure that your heads can take it.

 

A bit of a budget buster... I had planned on running this with the nice BW T5 World Class that I have, since it fits in the Z tunnel nicely. Now I find that I'm making much more power than I originally planned, and the WC won't stand up to that kind of tQ.

I found a 6-speed T56 for $700. More weight, unfortunately! Well, at least I'll be able to shift till the cows come home. I think I can get $500 out of this good condition World Class, so hopefully this is not too much of a $etback.

Where can I find the ratios on the T56 out of an 03 Z06? What rear should I run with a (now 2450) lbs car?

 

Well, i ran w world class T5 behind my 500 HP 383 with the same cam and in my 89 RS weighing 3600 LBS with me in it. Beat the **** out of it on slicks and stock clutch discs with a centerforce pressure plate and it never complained. BUT, i did not mega shift it but i did beat it to death. Took a long time before it broke.

 

Well, that would be VERY welcome news if I could keep the WC. Any leads on beefing her up a little without doing the damn $2000 GForce conversion?

 

Well, the problem is, the input shaft and the counter shaft are so close together it makes it a weak link, not to mention the skinny tail shaft. If your car is as light as you say, you will be ok for a while. I am not the only one who has beaten the dog snot out of these things. Look at the mustang guys, the old fox bodys and what not, they give them HELL and they last for a while. Not to mention the input shaft on a chevy T5 is a 1 1/8 vs the ford 1 1/16. It is just how well the trans was treated before too.

 

man, swoop that t56 asap.
it will be one of the best parts on your car. the stock t56 can take alot of abuse in stock form, t5 is ok, but a t56 awesome.
it takes lot to hurt it. i barely hurt mine last nite,
im at 490rw and was spinning 7k when it got damaged.
6k rpm dumps with dr's on street and track. i abused it but still runs, i just cant shift at 7k wot 3rd to 4th no more til i fix

 

Yea, it just doesnt have the lower 1st gear. But not all T5 had the 3 to 1 1st gear, some had a 2.75, i think the T56 is 2.63? Cannot remember.

 

Unfortunately, running the T56 (even for $700) costs quite a bit in the 240Z. I would need a very specific flywheel ($300), and I would have only one option for a clutch, and it isn't even a performance clutch. I would also need a Weir bellhousing, which is probably expensive. :/

I am looking hard at keeping the WC. As far as gear ratios go, I would rather have a close ratio 2.xx than a shorter 3.xx. All that tQ in a little car would make a big 1st gear just unusable.

 

Man, the 3.06 1st makes it go ultra fast to 2nd gear, especially in such a light car. But it will be fun no matter what.

 

check jegs. (can't remember the name, saw it tonight)its a little pricey but they now have an aluminum flywheel to use with a 2 pc rear main small block chevy. its 13.5 lbs. if you use the centerforce it is 35lbs. it sucks being dropped on your finger.i don't understand why you would need this other bell housing stuff when you're stuffing it behind a small block? no room?

 

Correct, sir! My 240Z's transmission tunnel is just nowhere near large enough to take a GM bellhousing, even if you were willing to do some precision work with a sledgehammer.

I've been told by several people now that they are running WC transmissions behind built 350's in these cars, and they hold up just fine so long as the trans is good to begin with. The lighter weight puts a lot less strain on the drivetrain, so the WC can take a lot more than 300 ft/lbs in my application.

 

Yep, like i said. I est mine for a long time, it went thru 4 engines before the 5th one killed it.

 

http://www.amazon.com/Small-Block-Ch...1908552&sr=1-1



for $5 you can get the book where chevy high performance documented various 350 builds with the goal of hitting 400hp out of a 350 cid.
going from memory, the 400hp mark was with mild compression but used 1-3/4 headers. I forget what the cam and intake was, pretty sure it used a 750cfm holley. I can look for you tonight. Generally, it was easy to build good broadband torque but when you wanted the 400hp goal you sacrificed torque at lower rpms for a narrow torque band at higher rpm which reached 400hp.
I highly recommend getting this book, it's great reference material for the price.