For 99-05 Twin Cam. 79cc, silver. High port flow gives great performance now, and more later when additional upgrades are done. Heads are fully assembled with springs and valves, and are available in silver or wrinkle black powder-coat. Compression ratios vary depending on cylinder heads chosen, pistons used and engine displacement; see Compression Ratios chart for specifications. 79cc heads work great with stock motors for 88" to 103" motors; 89cc heads work best for motors over 103" or with high-compression pop-up pistons. 79cc have 1.940" intake and 1.575" exhaust valve and springs for up to .650" lift (unless noted); 89cc have 2.000" intake and 1.605" exhaust and .640" springs. 79cc heads accept OEM rocker boxes. 89cc heads accept S&S rocker boxes only (PART #90-4110). Heads are machined for compression releases (sold separately); S&S rocker boxes required when using S&S compression releases. Do not include rocker arm components, intake manifold or gaskets. Heads include four long headbolts, and reuse four long OEM headbolts. Accept OEM intake manifolds. Sold in pairs. Made in the U.S.A.. NOTE: Must use S&S rocker boxes (PART #90-4110) if S&S compression releases are used - Part Number - 0930-0062
