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Old 01-27-2013, 06:18 PM
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Originally Posted by Joel78Vette View Post
Sir, can you explain also what you mean by the squish being too wide? Is there some rules about the squish in conjunction w/static compression?

I understand that the compression may be too high for that cam, but I couldn't afford the .051" thick gaskets at the time to bring me down where I felt more comfortable either. I know it sounds absurd to do all of the work I did for the sake of $60 or so and then not have the optimum motor that we all hope to build and enjoy.
Adding a 0.051" gasket to a 0.016" piston deck height would only compound your problems. It's a bad idea to use a thicker gasket to adjust static compression ratio because it widens the squish and the motor is more likely to detonate with the wider squish than it will from the decreased static compression ratio. The generally accepted range for squish on a SBC is 0.035" to 0.045", regardless of static compression ratio. You could do it with a 0.039"/0.040"/0.041" gasket thickness and a zero piston deck height or you could do it with a 0.026" gasket and a 0.014" piston deck height or you could do it with a 0.016" gasket and a 0.024" piston deck height.

Don't confuse piston deck height (zero to maybe 0.045") with block deck height (9.025" to maybe 8.980").
With 10.6:1 static compression ratio and the intake valve closing at 37, the dynamic compression ratio is 9.27:1. If you have not heard the motor detonating, then it's because you either have not had the motor under load or your exhaust system isn't allowing you to hear it.

Last edited by techinspector1; 01-27-2013 at 06:23 PM.
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