Kartboy's billet aluminum crank pulley reduces rotating mass by almost four pounds! (It's one pound, compared to the stock pulley at 4.9 pounds.) Precision CNC milled from a solid block of high-strength aluminum, then powder-coated for durability, the Kartboy crank pulley will hold up and look good doing it. Of course, dropping rotating mass from the engine allows the engine to rev more freely, and power that's not expended accelerating the crank pulley is freed up to accelerate the car!
Fits all 2013-2021 BRZ and FR-S cars, 2015-2021 WRX, 2011+ Forester, 2012+ Impreza, and 2013+ Outback non-turbo. (Basically, anything with an FA or FB Subaru engine.)