Torque Solution Water Pump Pulley - Subaru WRX 2015-2021 / Multiple Subaru FitmentsTorque Solution Lightweight Water Pump Pulley Applications: Subaru FA20DIT FB20 Engines (See Application Guide Below) Torque Solution Lightweight Water Pump Pulley is a nice and simple upgrade for Subaru FA20DIT FB20 Engines. Our pulley is approximately 37% lighter than the OEM pulley. Less engine rotational weight is a great way to improve throttle response and free up lost HP and TQ. Easy install by simply swapping in place of the OEM pulley. 6061