I recently bought a 318 that had just been rebuilt. Has been bored .040 over. The pistons are flattops that are about .1 down in the hole at top dead center. The head gaskets are .05 thick. The heads are 1976 318 heads with the numbers 4027163 on them. Id like to get the compression up in the 9's if I can without altering the short block. I do have a set of 302 heads if they would help.