Multiple U.S. Warehouse LocationsBroken ApexFree shipping on qualified orders over $100*
The GFB 3-piece underdrive pulley kit for WRX/STi models replaces crank, alternator and power steering pulleys (and belts) to significantly reduce rotating inertia and sharpen throttle response. CNC-machined from 6061-T6 billet, the kit can reduce inertia up to 85% and may underdrive accessories to lower parasitic load at high RPM, delivering a bolt-on livelier engine feel without compromising accessory performance.
GFB 04-10 WRX/STI 3 Piece Under-Drive Pulley Kit w/ Belts (Crank Alternator & Power Steering)
