The S&S Camshaft Gear Drive Kit increases valve timing accuracy in 1999-2006 Twin Cam 88 engines by eliminating timing chain lash and the loosely fit stock cam gears This is accomplished by replacing the stock cam drive sprockets and chain with light press fit S&S gears Because the chain, chain guides, and tensioner are eliminated, there is no longer a possibility for these parts to fail and damage other parts The S&S Camshaft Gear Drive Kit reverses the rear cam's direction of rotation, providing additional operating clearance between cam lobes As a result, higher cam lifts are possible with the gear drive kit Bolt in Camshaft set for 1999-06 Twin Cam, 180 psi cranking compression, no need for compression releases RPM range from idle to 4500 Great bolt in torque