S&S CYCLE S&S® Super Stock® Cylinder Head Kit For 3-1/2" and 3-5/8" Bore HD® '84-'99 Big Twins - Natural Aluminum Finish - 90-1004

These S&S^® Super Stock^® cylinder heads for 1984-'99 HD^® Evolution^® Big Twin engines feature a specially shaped combustion chamber and require special pistons that must be purchased separately. (Not compatible with stock style flat topped pistons) Large 2.000" intake and 1.605" exhaust valves and high flowing ports supply plenty of air for big inch engines. Compatible with cams with lifts up to .650". Compatible with stock 3-1/2" or 3-5/8" bore engines. Order appropriate gasket kits separately for your specific bore size. Natural aluminum finish.

• S&S heads give great performance, and work with additional upgrades
• Kits are fully assembled, and include stainless steel valves and high-lift springs (up to .640 lift)
• Intake manifold, pistons and gasket kits are sold separately; gasket kits contain head gaskets, base gaskets and exhaust pipe gaskets (rocker box gaskets are not included due to the variety of available rocker box styles)
• Must reuse stock headbolts
• S&S Super Stock piston kits are required and include 10:1 ratio pistons, rings, piston pins and clips (sold separately in pairs)
• Made in the U.S.A.

Specs