Perrin Lightweight Crank Pulley Black WRX (2002-2014) STI (2004-2018) Mazda the included silencer helps to

the included silencer helps to significantly reduce noise

they also include precise control dump valves

Subaru WRX/STI 2008-2014

Mishimoto Subaru WRX Tuning Kit

Perrin Lightweight Crank Pulley Black WRX (2002-2014) STI (2004-2018) Mazda the included silencer helps toPerrin's lightened crank pulley for the Subaru WRX STI LGT is engineered to reduce rotating mass, increasing horsepower and torque. Made from 6061T6 aluminum and weighing 1. 2lbs, Perrin crank pulley is more then 4lbs lighter then the stock crank pulley. Perrin's pulley is not underdriven and will not affect the life of your engine. The pulley is simply a redesigned, lighter version of the stock crank pulley. Aftermarket underdrive pulleys are prone