I'm guessing you guys are right. Pulled the head tonight, currently tearing down the car to totally rebuild and want to freshen up the engine for hopefully a supercharger along will some forged pistons. Checked out the head valves are standard size standard bore. Thank god the bores on the engine look really really good actually. Thanks for the help just one of those curiosity things I always wondered about. Time to get out the degreaser you can't believe how filthy this engine is.