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Old 11-29-2010, 08:29 PM
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Quote:
Originally Posted by olddog View Post
I don't have the expertise to give you an answer, but I do know enough to tell you that you need to give more information, if you want reasonably accurate answer.

Aluminum heads or cast iron?

The combustion chamber and piston combination can give more or less swirling and quench, which can have an impact.

Cam timing can give a much lower dynamic compression than the static compression.

All these factors combine to make big differences that is over my head.

My rough rule of thumb is stay around 9.5 with iron head and 10.5 with aluminum heads for a street engines. I could be dead wrong depending on your combination.
Well I was thinking of using flat top's with -58cc 255cc AFR aluminum heads but that would give me about 13:1 compression, with a custom ground cam from Comp Cams. And then I remembered that if it's too high you'll need race fuel.
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