maybe... never seen it. Can't buy a head gasket as thin as the approx. .015 original tins. So ya give back .010 of the .040 even if the .027 "thin" gaskets are used. IF the "over the counter" Fel Pro's are used, they are .050 thick. Now it's a gain of about a whopp'n .010. Many cut 'em .060 and never an issue. I wouldn't raise an eyebrow to .040.