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Old 09-15-2008, 07:19 PM
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You can guesstimate the squish depending on whether or not the block has been decked and what kind of piston you used, along with the compressed thickness of the gasket.

If you used a cheap, rebuilder type piston, then the piston compression height is probably around 1.540" and the squish will be in the toilet with a virgin, un-cut block and a standard 0.040" compressed gasket.

Add up the stack. Half the crank stroke is 1.740". The rod is 5.700". The piston is 1.540". This adds up to 8.980" Subtract this from a virgin block deck height of 9.025" and you get the piston down in the bore 0.045" at TDC. Add a standard 0.040" gasket to this and the squish (or lack of squish thereof) comes out to 0.085". If this is what you put together, chances are that the motor will detonate on pump gas at 10.0:1

If you used quality pistons that were manufactured with a piston compression height of 1.560" (or 1.561" in the case of KB hypers), then you may slide by with a squish of 0.065". If you used 1.560" pistons and a head gasket thinner than 0.040", you should be fine on pump gas.

As a side note, in my opinion, you did a good job of matching the cam to the c.r. You should also get a nice rump-rump out of it with the 106* LSA.

Last edited by techinspector1; 09-15-2008 at 07:39 PM.
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