nm9stheham said

Felpro 1008's will raise compression by about 0.2 points and cranking compression about 4 psi on average. Just noticeable in the butt-dyno.

Mr Gasket 1121G's will raise compression by about 0.4 point and about 8 psi of cranking compression. A definite change will be felt. These are thin and some have reported sealing issues; so I can only recommend that the heads and block be known to be good and flat before using these. If the heads and block have not been checked or surfaced, then you cannot count on them being flat.

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