.514" valve lift. For 84" to 93" strokers with no greater than 9:1 CR. Best gains occur in the mid range from 2500 to 5000 rpm where most riding is done. Relatively quiet and easier on the valve train than most other cams with lifts as high. Solid lifters or aftermarket hydraulic tappets are recommended; valve spring spacing and other normal clearancing checks required. 2500-5000 RPM.

.640" valve lift. Big inch engines with 10.5/11.5:1 CR. Smaller engines with 11:1 to 12:1 CR. With lower TDC lifts; faster ramps and shorter duration it builds higher cyl. pressure and requires less CR and offers a more linear power delivery as the 631. Supplied with the S&S 124" SSW+ engines. 3000-6000 RPM.

.453" valve lift. Engines up to 88" with up to 8.5:1CR. Good low and midrange torque. For hydraulic lifters; but solids can be used.

510." valve lift. IOG = gear drive cams with Inner & Outer drive Gears. Complete kit with installation hardware; bearings and gasket. Bolt-in 88" to 95" with up to 9.7:1 CR (unported heads) 3000-5500 RPM. The gear drive system is in fact a revolutionary different and much more reliable construction. Especially in high lift/performance applications; when compared with the OEM chain-drive design. A gear driven camshaft is stronger and will not give any of the mechanical problems connected with the OEM chain driven camshafts. The S&S gear drive kit will increase valve timing accuracy; and therefore horsepower; by eliminating the timing chain lash and loosely fit stock cam gears. The only downside of gear drive is that you may experience a slight increase in mechanical sound; this is why OEM is using a chain. It has no other mechanical advantages whatsoever. Since the chain guides and tensioner are eliminated there is no longer the possibility for these parts to fail and damage other engine parts. The S&S gear drive kit reverses the direction of rotation of the rear cam; providing additional operating clearance between cam lobes. As a result; higher cam lifts are possible with the S&S gear driven cams. Note: With the exception of the 475G and 510G cam; adjustable pushrods (like MCS 503573) are required to compensate for the smaller camshaft base circle of these cams. Note: Material may have to be removed from the inner surface of the OEM gear cover before installation o

.570" valve lift. IOG = gear drive cams with Inner & Outer drive Gears. Complete kit with installation hardware; bearings and gasket. Bolt-in 88" to 103" with 9:1 to 10:1 CR. 3200-5700 RPM overall power increase. The gear drive system is in fact a revolutionary different and much more reliable construction. Especially in high lift/performance applications; when compared with the OEM chain-drive design. A gear driven camshaft is stronger and will not give any of the mechanical problems connected with the OEM chain driven camshafts. The S&S gear drive kit will increase valve timing accuracy; and therefore horsepower; by eliminating the timing chain lash and loosely fit stock cam gears. The only downside of gear drive is that you may experience a slight increase in mechanical sound; this is why OEM is using a chain. It has no other mechanical advantages whatsoever. Since the chain guides and tensioner are eliminated there is no longer the possibility for these parts to fail and damage other engine parts. The S&S gear drive kit reverses the direction of rotation of the rear cam; providing additional operating clearance between cam lobes. As a result; higher cam lifts are possible with the S&S gear driven cams. Note: With the exception of the 475G and 510G cam; adjustable pushrods (like MCS 503573) are required to compensate for the smaller camshaft base circle of these cams. Note: Material may have to be removed from the inner surface of the OEM gear cover before instal

.500" valve lift. Bolt-in; good torque. 74" to 89" with 9:1 to 10.5:1CR and 89" to 100" with less than 9.5:1CR. Used with solid or hydraulic lifters with adjustable pushrods. Clearance checks recommended. Note: Stock 86-03 XL valve springs are okay to .510" valve lift.