Go Fast Bits Underdrive Pulley Kit w/ Belts 2008-2014 WRX / 2008-2021 STI

Description:
This GFB Pulley Kit comes with the crank, alternator and power steering pulleys as well as the belt needed for install. Having large heavy pulleys spinning takes away power that is better spent moving the car. This kit takes care of that by replacing the crank pulley with a lighter version that underdrives the power steering and alternator yet leaves the A/C compressor spinning at normal speeds.

Features:
- The crank pulley weighs .86 lbs
- Power steering pulley weighs .37 lbs with 18% underdrive
- Alternator pulley weighs .14 lbs with 16% underdrive
- The total mass of GFB pulley kit is 1.38 lbs
- Mass savings for STI models: 5.31 lbs
- Mass savings for WRX models: 4.43 lbs
- AC compressor will still operate at normal speeds
- Includes new belt
- Black finish

Specs:
- Stock Crank Pulley: 5.51lb (STI) / 4.63lb (WRX)
- GFB Crank Pulley: .86lb
- Stock Power Steering Pulley: .81lb
- GFB Power Steering Pulley: .37lb
- Stock Alternator Pulley: .36lb
- GFB Alternator Pulley: .14lb
- Alternator Underdrive: 16.5%
- Power Steering Underdrive:  18%

Applications:
2008-2014 WRX
2008-2014 STI
2015-2021 STI
2009-2013 Forester XT
2005-2009 Legacy GT
2005-2009 Outback XT