The head is an aluminum Knudsen, originally 7.7 to 1. When I bought it, the PO had taken it off a '48 engine with head studs. He used a hammer and screwdriver. I had it milled after it was welded up. The machinist guesses it at about 8.25 to 1. FYI, Norfleet Cams in Dallas, TX can regrind your stock cam to an Isky 400 Jr. grind.
