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Go Fast Bits 02-10 WRX/STI 2 Piece Under-Drive Pulley Kit w/ Belts (Crank & Alternator)


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GFB lightweight pulley kits are made from aircraft-grade 6061-T6 aluminium and offer faster acceleration through significant weight reduction on the crankshaft. The effect is similar to a lighter flywheel, and the car feels more lively and willing to rev.

Most of our kits are underdriven, which means the accessories are driven slightly slower to reduce parasitic losses. It should be noted that our underdrive pulley kits do NOT adversely affect the operation of the accessories. If they did, we would not sell them!


* Improved throttle response and acceleration through significant reduction of rotating mass

* Engine feels more free-revving

* Under-driven kits offer more power through reduction of parasitic losses from the accessories with NO adverse affects on their operation



2004-2005 WRX

2006-2007 WRX

2004-2007 STi

2004-2008 Forester XT

This product can expose you to chemicals including Lead, which is known to the State of California to cause cancer and birth defects or other reproductive harm. For more information go to

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