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Old 04-23-2013, 07:30 PM
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Originally Posted by gearheadslife View Post
one question,, if my 18cc domepistons give 10.2 to 1 with a 118 chamber
how is a 112 chamber only 10.44 to 1.. what am i missing??
I don't know. I'll run through it again for you to be sure.
I figured the short block at 4.280" x 4.250".
(.7854) x 4.28 x 4.28 x 4.25 x 16.387 = 1001.99 cc's
chambers = 112
Pistons = 18cc dome, so we will deduct the dome from the chambers, so that the piston is zero and the chambers are 94 cc's. Just visualize slicing the dome off with a sharp knife and glueing it into the combustion chamber. That makes the piston flat at zero and the chamber at 94.
The piston deck height is 0.010", so it figures like this....
(.7854) x 4.28 x 4.28 x 0.010 x 16.387 = 2.35 cc's
The 1027 gasket is 9.7 cc's
1001.99 + 94 + 2.35 + 9.7 = 1108.04
Deduct 1001.99 from 1108.04 and find 106.05
Divide 1108.04 by 106.05 and find 10.448:1 SCR

Maybe you figured it wrong to begin with. Or maybe my math is wrong.

"and tech. what made you pick "that" afr head and not the other two ovals??"
Street motor. Needs torque, not hp, although those tiny little heads ended up making a ton of hp too. Bigger heads will make more hp, but that's not what you need on the street. If you want a race motor, then let's stop fartin' around and build a 632 and make 900 hp.

Last edited by techinspector1; 04-23-2013 at 07:45 PM.
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