Cylinder fits to piston no machining requiredTC3 cam support plate and TC3 oil pump to ensure consistent oil pressure and engine longevityIncludes an S&S 4'' big-bore cylinder kit with 10.5:1 pistons, S&S 585 Easy Start cams, S&S Quickee Pushrods, and Premium Hydraulic tappets to make the most of the added displacement Made in the U.S.A.Not for use with S&S 79cc heads.Can be used with stock heads.