Opps. Personally I have very poor luck with copper head gaskets. Water sealing is the problem no matter what product I used. Hussey will make them in any thickness you want.
Best Gaskets makes a 302 which is nice and I am currently using. If you want a large bore I would contact Don Ferguson Jr. @ Wilmington Forge as he is a supplier of Best. He has run a very high % of nitro with these and they hold just fine. Good Luck
