compression estimate

[cdg1984]

So can any of you fine gentelmen ( or classy ladies, for that matter ) give me a rough estimate of what my compression ratio would be if I put a set of 462 double humps on my sbc350. Its around an 86 or 87 with stock pistons and crank. Im pretty sure it has a small cam in it, but i bought the engine used and it went through like 5 people before it came to me, so I dont know all the specs. The head specs are: 2.02 in. 1.60 exh. and has been decked to make the chamber 57cc. Remember, I said ROUGH estimate. Sorry for my ignorance on the cam. Thanks in advance.

 

[cdg1984]

Oh, and what do you think would be a good cam to go with them for a street car.

 

[dogsht]

www.kb-silvolite.com has a simple fill in the blank compression calculator.

 

[CHRIS.O]

9:1? I dunno. What piston do you have? Flat top 4 valve relief? 2 valve relief? 4 valve relief dish? I know you said rough but theres a big difference in 9:1 and 10:1 and it could very well be a point or more based on your pistons.


Cam selection requires a good amount of info. Rear gear, actual compression ratio, stall, drag car, street car, where do you want the power?

 

[cdg1984]

Thanks dogshit. Chris, unfortunately, the pistons are dished. PS. like the avatar...I literally lol'ed when i saw it.

 

[chevy2480]

Well most stock 350 are around 8:1 with dish pistons with 76cc heads and yours are 57cc. That a 19cc difference and if memory serves me right 1cc is worth .05 on compression that puts you at 8.95:1.

 

[cdg1984]

Thanks a lot, man. Appreciate it.