I found out that I have a 383 in my 79 Camaro. I was wondering what type of horse power I would be making and if I switched from 76cc to 64cc heads would do. The engine is a 1970s 350 bored 30 over with flat toped pistons. Forged rods and a 400 crank with a push on harmonic balancer. It has a .015" head gasket and old after market over the counter 882 heads with new valve job and springs. Has a summit racing 1103 cam. Holley 600cfm, edelbrock eps intake, hei, 30w race oil with a 4.3 high torque starter. Connected to a 4 speed close ratio Saginaw with 11" clutch and hurst shifter with posi and 4.11s. Thanks
You're pushing the compression limits right now for pump gas, especially with iron heads. If your pistons are .025 in the hole, with 76 cc heads you're close to 10.29:1. If the block has been zero decked you're at 10.90, too much for the pump.
If you reduced the heads to 64 cc you'd be at 11.8:1 and 12.67:1 respectively. Strictly race gas territory, even with aluminum heads. A thicker gasket would bring you down around .9 with a .041 gasket.
Also, if you're zero decked your quench area is too tight, .015 with your current head gasket.
68NovaSS, I'm not getting anywhere near that high of compression ratio figures with 76cc heads(882's), the .015" x 4.100" gasket, and assuming standard .020"-ish deck height 6cc eyebrow flat-top piston(nothing was said about block decking)...only about 9.7-1 comp right now. (something not right on your calculator maybe, like valve relief volume???)
I would guess 330 or so HP right now, the 882's really suck.
It would jump to 11-1 with a 64cc head, would be pump gas safe if head was aluminum.
79CamaroMatt,
Cam, intake, carb change to 220+/230°+ @ .050" and .500"+ lift, Performer RPM intake and 750 carb and a 195-200cc+ intake runner 64 cc chamber aluminum head and you'll pick up an easy 100 hp.
I'd stick with the 76cc heads. If you want a better flowing head afr makes a 75cc head. I'd imagine you have the 64cc heads on the shelf doing nothing though, right. If the pistons are .025 in the hole which I doubt they are being a stroker engine. They're probably more like .017 or so then your pushing pump gas and need to be running good fuel with a good tune.
Do you think the engine lacks power or you just want more?
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