When the time comes for the horsepower you know that your Thumpr Cam will deliver. The Thumpr GK-Kits are available for many Ford applications and the kit includes the Thumpr Cam of your choice along with the appropriate gear drive and carefully matched lifters. Each gear drive uses heat-treated billet steel gears to ensure the ultimate in durability and timing accuracy. A three keyway crank sprocket allows up to 4 degree of advance or retard. Looks pretty cool. Contact COMP Cams at (800) 999-0853 www.compcams.com.