These S&S® Super Stock® high performance cylinder heads are designed specifically for S&S® T-Series T2 long block engines for 2007-'16 HD® big twins and 2007-'16 engines with S&S® 4-1/4" bore Hot Set Up Kit installed. 2.000" intake and 1.605" exhaust valves coupled with S&S® ports, supply plenty of air for these big motors. Not machined for S&S® compression releases. The manifold mounting surface is machined to stock dimensions, so a special manifold/throttle body is required for engines that are not stock height. S&S® High performance valve springs allow the installation of camshafts with up to .650" lift. Compatible with stock rocker boxes, exhaust, and intake manifolds. Black wrinkle coat finish matches stock black engine components