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Old 02-18-2007, 01:12 PM
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jj, is it stock bore with stock-type Chevy 4-eyebrow pistons?
Do you know how far down in the bore the piston is at TDC?

If we assume a stock short block with a piston deck height of 0.030", 7 cc's in the piston crown, 58 cc heads and 3.5 cc's in a 4.100" x 0.016" shim gasket, the static compression ratio will be 10.61:1.

Like Curtis73 said, the cam needed at this level of compression will be way beyond the capabilities of the heads. You'd have a very soggy bottom end due to the duration and intake closing point required to prevent detonation, plus the motor will run out of breath just as the motor starts to come up on the cam.

This looks like a very bad idea. To make the heads work, lower the compression with dished pistons down to around 9.0:1 and use a short cam that makes power from 1,000 to 4,500.
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