3 This is why you degree a camshaft. JGM has chosen to go with a custom flat-tappet, mechanical cam (PN 33-000-5) from Comp Cams. Based on Jim Grubbs' findings, he has elected to retard the cam 2 degrees to improve high rpm horsepower numbers. This means sacrificing some torque. What we want most from the 427 is horsepower and a broad torque curve, however.