AEM Black Tru-Time Cam Gear - 92-01 Honda Prelude Si VTEC/ Base & SH H22A1 H22A4 - 23-801BK**NOTE: SOLD BY EACH GEAR. IF YOU NEED A PAIR, YOU NEED (2) TWO QTY** AEM Tru Time Adjustable Cam Gears increase horsepower and torque without having to change the camshaft(s) and are must have items for engines that are milled, forced induction, high compression and or utilizing aftermarket competition cams. Tru Time cam gears enable users to match cam timing with their vehicle's tuning state by advancing or retarding the cam profile(s) in one degree