Coo, yes, peak numbers. It is wood to APC, but I see that you are getting considerably more RPMs when comparing the 15/6 size. Witholding 300 RPM for the difference between wood and APC, you are still getting 800 RPM more than me. Will altitude effect my readings? I'm at 1000 feet ASL. Perhaps my trusty old Saito has too many hours on it. Joe