S&S S. Stock Cylinder Heads Black 89cc (90-1106)

S&S - SUPER STOCK™ CYLINDER HEADS FOR TWIN CAM

• 79cc have 1.940 inch intake and 1.575 inch exhaust valve and springs for up to .640 inch lift; 89cc have 2.000 inch intake and 1.605 inch exhaust and .640 inch springs.
• Sold in pairs.
• 79cc heads work great with stock motors for 88 to 103ci motors; 89cc heads work best for motors over 103ci or with high-compression pop-up pistons.
• High port flow gives great performance now, and more later when additional upgrades are done.
• Accept OEM intake manifolds.
• Compression ratios vary depending on cylinder heads chosen, pistons used and engine displacement.
• Does not include rocker arm components, intake manifold, gaskets or headbolts (requires eight long OEM length head bolts).
• Heads are fully assembled with springs and valves, and are available in silver or wrinkle black powder-coat.
• Made in the U.S.A.
• Heads are machined for compression releases (sold separately); S&S rocker boxes required when using S&S compression releases.
• 79cc heads accept OEM rocker boxes 89cc heads accept S&S rocker boxes only (PART #90-4110).

NOTE: This project requires a skilled technician. It is the responsibility of the person assembling the parts to check all clearances and assembly specifications.

NOTE: Must use S&S rocker boxes (PART #90-4110) if S&S compression releases are used.