[Steve C.]

From the internet....

For every action there is a reaction. Thicker gasket will lower compression, but increase quench area.


"Chamber volume is the major component in determining static compression ratios. Situations where quench must be sacrificed in order to keep compression in check to satisfy a competition rule or accommodate existing parts, do arise. Increasing head gasket thickness is an easy and affordable way to reduce compression. However, reducing quench will also reduce efficiency and lessen resistance to detonation."

https://www.enginelabs.com/engine-te...ston-and-head/
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