Factory I.D. 3863151 for: 327c.i., 1965-68, factory 350 HP; 327c.i., 1967-68, factory 325 HP. 1,800-5,800 RPM Operating Range 222/222 Duration at .050". 114 Degree Lobe Separation Angle 0.447/0.447 Valve Lift Factory Muscle - Reproduces factory original muscle car camshafts that are designed to work with the high compression engine of the 1960's and 1970's to produce a rough idle. Old School, High Tech - While these grinds replicate the sound, efficiency and drivability of factory camshafts, the COMP Cams Factory Muscle were created with advanced software to avoid factory design compromises. Fits Chevrolet GEN 1 Small Blocks including the 262, 265, 267, 283, 302, 305, 307, 327, 350 and 400. Does not fit LT1/LT4, or factory roller Small Blocks built from 1985 and newer. Made in USA