Thread: What engine for a '76 Vette?

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I'm looking to buy a Vette here in the next few years and I want to budget out everything so I know how much I'll be spending.
What does everyone think about this build sheet for a 383 stroker?

Air Flow Research 190 with 2.02/1.60 Valves and 190cc Intake runners.
Comp Cams Hyd. roller 236*/242* @0.050 & .520/.540 w/ 1.6:1 rr
TRW forged pistons
Lunati 5.7in rods
Scat 8060 crank
Holley Stealth Ram MPFI
Hooker 1 3/4" headers and sidepipes

I'm pretty set on the heads, I could use other suggestions on a cam, Rods, Pistons, and Crank.
I like the look of the Holley setup, and I think I want to go FI. Any other recommendations for FI setups?
The Headers and sidepipes are engraved in stone, not changing my mind.

Advice, please.

I would go with a lighter weight piston like an SRP. TRW's are pretty heavy. Everything else looks pretty good and your engine should make over 450 hp. I would talk with AFR about adding their revkit as a hydraulic roller won't go much over 5800 rpm without a revkit. That cam could easily be pushed over 6000 rpm. As for FI, I would check out Edelbrock's EFI system as well as the Holley. I think Eddy's customer service is much better. But if you are sold on the Stealth Ram, go for it. They make some good hp numbers. I think you mean AFR 195 heads--I have the 190's but they stopped making them a couple of years ago. My 383 made 450 hp and 468 ft. lbs of torque with a Comp Magnum 280 cam, 10.6:1 compression with forged SRP flat tops, and Edelbrock RPM intake and 750 carb. BTW, AFR is coming out with a new head design which is supposed to make awesome hp and torque. Give them a call. I think they are available now.

Thanks for the feedback.
Of those heads, does it matter what plug style I would get? L98 angle or straight?

Anybody else have feedback on the cam, pistons, or crank? Is there a certain piston style I should get? flat, domed, recessed valve?

Yeah, I've got a question. How can you choose a cam before you have figured the squish and therefore the exact static compression ratio?

This is not a trick question. The cam should be the very last item you buy for the motor and should be used to set the dynamic compression ratio of the motor. The DCR is where you find out if you have a motor or you don't.

I haven't really figured out a cam. I just threw in a cam spec that was in the range that I thought I would need. And speaking of such, do you know of a program or site that will help me with the equations for calculating such? Been a few years since my IC engine design course, and we didn't cover cams much.

If I were building an engine, I would first decide how it is going to live its life. Do I want a torquey, daily driver or a high reving horsepower motor. What is my budget? If you're below $3000, I would't run the motor above 6500 rpm. Then, I pick a cam that gives me the power curve I want. Then, I chose components that match the cam. If I chose a 6500 rpm cam, I would build a motor to match it. 180ccish heads, 9.5-10:1 comrpession, a 6500 rpm intake, and a larger carb. If I went with an off-idle to 5500 rpm cam or so, I would go with 170cc heads like the Vortecs, aim for a max compression ratio of 9.5:1, and a idle to 5500 rpm intake. When building an engine, I personally believe the cam should be the first part selected. Then, build the engine on paper and if it doesn't match your budget, start over with a different cam.

This may be way off topic for you, but if I was going to do a new motor for C3 Vette, I think I would be looking real hard at an LS2 or LS6 crate motor and associated T56 six speed. Or be looking for an LS1 drop out from a late model Corvette. It's not exactly a straight bolt in, but enough people have done the swap that the ground is broken. You will end up with a car that is wicked quick, but still has decent street manners and will even get good gas mileage, plus you would have something that is a little more unique than the usual Vette with a SBC. It would also give you the EFI you are talking about. I am just now driving my LS1 Studebaker and love it, and the Wow! factor when people see it has me grinning from ear to ear. Just offereing it up for what ever it's worth.

Pat

Originally Posted by JoJoDaClown

Thanks for the feedback.
Of those heads, does it matter what plug style I would get? L98 angle or straight?

Anybody else have feedback on the cam, pistons, or crank? Is there a certain piston style I should get? flat, domed, recessed valve?

The posts here offer some good advice, but to answer your question, angle plug heads can create some clearance issues and you have to order headers that work with angle plug heads. Personally, I would use straight plugs. You will need to match heads to piston-type for figuring compression. With a 68cc chamber, you may need a dished piston, but with a 72cc chamber, a flat top may be in order. Once you have some possibilites, start combining them with cam specs in the DCR program mentioned in a previous post. You should not have a DCR above 8.5 for pump gas, 8.25-8.5 you should figure on running 92 octane. The closer to 8:1--89 octane, under 8:1 you are more likely to be able to run 87 octane. Now these are just ballpark figures, and all engines are different. What might work for one may not work for another. When you think you have a combination that might work for you, post it and we can give you some feedback.