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Old 06-24-2013, 01:07 AM   #8
btwilson86
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I understand that this thread is asking about how much physical material can safely be removed from the cylinder head, but since it is somewhat related I'm wondering if anyone on here knows how thick a stock head gasket is when it's properly compressed between the block and cylinder head.

I assume that a 1.4mm metal head gasket does not compress beyond this thickness when properly installed, so that the result would be a 1.4mm gap between the cylinder head and the engine block. If you have .011" off of the cylinder head, and .006" off of the block, then a total of .017" (or 0.4318mm) needs to be compensated for. If the stock head gasket is .9682mm or less when compressed, then your compression ratio should remain the same or be slightly decreased a minuscule amount. If the stock gasket is thicker when compressed, then your compression ratio will increase slightly, and your cylinder head will be closer to the block than stock, which could create interference in a non-interference engine with very close tolerances (I do not know whether or not the 7M falls into this category).
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