I did the calculations when switching from a thick copper head gasket to a thin composite type. My recollection is that the thin gasket was 20 thou thinner than the thick gasket and bumped compression by 1/2 point.
This agrees with the JS Motorsport info. He suggests milling 40 thou from the head will increase Cr. one point, as in from 8.5 to 9.5
So .020" off the head combined with an .020" thinner gasket should do it.
Glen
This agrees with the JS Motorsport info. He suggests milling 40 thou from the head will increase Cr. one point, as in from 8.5 to 9.5
So .020" off the head combined with an .020" thinner gasket should do it.
Glen
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