S&s cycle heads 06-13tc 89cc slvr

S&S 89cc heads have a whopping 264cfm flow rate (compared to 182cfm for stock H-D® heads), larger valves and .640" lift valve springs. S&S recommends S&S Easy Start cams or manual or electric compression release system in order to maintain reliable engine starting on high compression applications. FEATURES AND BENEFITS: ??Heads can be decked up to .060" to increase compression ??89cc heads have 2.000" intake and 1.605" exhaust valves ??S&S 0.640" lift valve springs ??Stock Harley-Davidson® rocker boxes can be retained if S&S manual compression release or S&S Easy Start cams are used. Must use S&S valve cover gasket kit part #90-4120 with stock rocker covers ??2006-'13 heads are machined for 2008-'13 FL top motor mount ??Includes 4 long headbolts for installation ??Includes rocker base gaskets pn #90-4120