The thickest I can find. I'm not 100% sure on it yet. The block required .025" to square it up. I don't know where the deck height is yet as it has not been back to the shop. I was TOLD the head cc'd at 54 cc's but I haven't had a chance to measure the chambers......that was before the port work and valve job, so I might be in better shape than I think. At least I hope so. lol
