are you sure on that number...My cam has .538 of lift on the exhaust side and I use to run it on stock heads all day long...I thought I heard somewhere that it was larger than that.[/
Good info, to know. Thanks. Valve guide to retainer clearance, (on mine, home assembled) would be about .040" clearance at full lift. (seems to close, to me) I played it safe, in my case.