Thanks Cab "You Da Man" My Machenist miked the skirts and gave them a good to go. I was thinking the low comp MW was 11.5 to 1. Is this correct? I've got a set of milled 915 heads they cc about 70. They should get me where I want to be. The 2.14 1.81 valves will be dang close to the bore If they work at all with the orig. 525 lift. More measuring required!