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Old 03-18-2009, 12:56 PM   #19
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Join Date: Jun 2006
Location: whitby
Posts: 690
Originally Posted by BigD View Post
Again please provide the math. I think my estimates were all pretty reasonable and I end up at a pressure ratio of over 1.9. You can't just pull out boost numbers out of thin air. 15PSI in an efficient DOHC head (if I remember correctly, I assumed .97 volumetric efficiency, which is pretty conservative) of a 3.2 at 7000 rpm at sea level is going to make a hell of a lot more than 400hp.
I used a basic equation with your numbers in the equation, i didnt just make up the numbers.

10 psia + 14.7 psia = 24.7 psi absolute pressure in the manifold

24.7psi/14.7 = 1.68 pressure ratio

Last edited by ///tyron; 03-18-2009 at 01:08 PM.
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