Thread: Twin Plug?
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911nut 911nut is offline
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Join Date: May 2001
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Quote:
Originally Posted by drmatera View Post
I expect I'll need about 20psi to reach my goal of 650hp give or take a few psi
Here's the formula for calculating effective compression ratio:

effective comp. ratio = [boost/14.7+1] x static comp. ratio

Twenty psi with a static compression ratio of 9.7:1 yields an effective compression ratio of 22.90:1.

I think temperature rise in the cylinder at peak compression will yield uncontrollable temperature with resulting detonation. Also, will the structure of the engine survive these forces?

There are others who have obtained 650 hp using a 7:1 compression ratio and 1.4 bar of boost on a 3.3L engine, which is a more cost effective alternative.
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Last edited by 911nut; 11-27-2011 at 02:17 PM..
Old 11-27-2011, 06:00 AM
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