Designed as bolt in cams for engines with 103'' and stock 9.7:1 compression ratio up to 10.5:1Works with stock, un-ported heads, but is great for S&S CNC ported headsPower in 3000 rpm - 6000 rpm rangeMade in the USARequires high-lift valve springs.Coil bind, valve-to-valve clearance, and valve-to-valve piston clearance will require checking.