I went with the steel shim head gaskets to help raise the compression a little since for some reason the 77 440 wasn't a good compression motor even the new pistons are still way below the deck but it's supost to be anywhere between 8.5 to 9.0 compression with the new pistons hoping 9.0 with these head gaskets and hoping the cam and other accessory's wake this motor up I'm still wondering an approx horsepower thisotor will put out without the nos