Tested on the dyno, street and track before being offered to the publicWorks with stock valve springs and stock non-adjustable pushrodsRecommended for S&S 883 to 1250 conversion kitsBest performance gains 3500-6500 rpmBolt in cam for '00-'20 models onlyMade in the USAInstaller must check coil bind, valve-to-valve clearance, valve-to-piston clearance and cam lobe to case clearance.