Grimmspeed Blue Lightweight Crank Pulley WRX 2015-2021 / BRZ 2013-2018 / FR-S 2013-2016 vendor_South Bend Clutch Part #: 566 311 A27

Part #: 566 311 A27

Supports higher horsepower and boost levels

Engine Type: 4-Stroke

Note: 2002-2007 WRX & 2004-2007 STI - Requires Subaru part number 21328AA140

Part #: PSR-216BFWAOT270

Grimmspeed Blue Lightweight Crank Pulley WRX 2015-2021 / BRZ 2013-2018 / FR-S 2013-2016 vendor_South Bend Clutch Part #: 566 311 A27Your factory crank pulley is responsible for transferring energy from your crankshaft to your water pump, a c compressor and alternator. It does this by way of a rubber belt and it does it's job well. The drawback to the factory pulley is that it's quite heavy. Reasons for this include less expensive manufacturing and using the pulley's mass to smooth out 'noise' in the accessory system (NOT to be confused with functioning as a harmonic dampener,