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Hi Jon -

Sometimes the gasket selection depends on if you need to adjust the spacing between the head and the block, usually to obtain the correct compression ratio.

The multi-layer steel (MLS) gaskets generally get a lot of recommendations.

I’m sure that a lot of expert engine builders will chime in here on this topic.

My new engine build used Cometic C58971-056 (.056” thick). I thought that the standard ones (e.g. Fel-Pro) are about .039” thick.... but I am prepared to be corrected.

Rocky
Multi-layer steel head gaskets (MLS) require that the block and heads are finished to a finer surface finish than the original finish, this is because the steel doesn't yield to the shape of the surface it is clamped to the way that composite head gaskets do. So unless your block and heads have been resurfaced to attain this finer finish you cannot use MLS head gaskets.

MLS head gaskets are indeed a "tough" gasket, but their main benefit is for combining aluminum heads with an iron block. The two dissimilar metals expand when heated at different rates and in different amounts, the layers of the MLS head gasket allow the aluminum heads to "float" in relation to the iron block, this is not needed when the heads and block are both manufactured from iron.

My recommendation is the very common Fel Pro part no. 8347 composite head gaskets, which I believe have an 0.048 inch compressed thickness.

FYI the OEM head gaskets were supposed to have an 0.038 inch compressed thickness. And the OEM deck clearance was "nominally" 0.035 inch, for a nominal total clearance of 0.073 inch. When I'm ordering pistons I shoot for no more than 0.025 inch deck clearance, which when combined with the FelPro gasket's 0.048 inch compressed thickness results in 0.073 nominal total clearance, same as the OEM spec.

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