Your factory crank pulley transfers energy from the crankshaft to the water pump, a/c compressor, and alternator via a rubber belt. However, it's quite heavy. The GrimmSpeed Lightweight Crank Pulley slashes the system's rotational mass, enabling your engine to speed up and slow down the rotating assembly faster. Key features include a 75% reduction in rotating mass (it weighs just 1.1lb compared to the 4.4lb OEM pulley), precision - machined 6061 T6 aluminum for high - quality construction, a hard anodized finish for durability and corrosion resistance, a design that allows use of the GrimmSpeed Crank Pulley Tool, and a perfect factory fit for easy installation. The engineers focused on optimizing the moment of inertia by keeping the mass close to the pulley's center without sacrificing strength. This results in a pulley that fits well, looks great, and enhances throttle response. Fitments include 2013+ Subaru BRZ, 2015+ Subaru WRX, and more specific Subaru models with FB/FA engines, plus 2013+ Scion FR - S.
Using your GrimmSpeed Lightweight Crank Pulley is straightforward. First, make sure your engine is cool before starting the installation. The pulley is a direct replacement for your factory one, so it should fit right in. Simply remove the old pulley and install the new one. When installing, use the GrimmSpeed Crank Pulley Tool if needed. As for maintenance, there's not much to do. The hard anodized finish resists corrosion, but it's a good idea to check it occasionally for any signs of wear or damage. If you notice any issues, get in touch with the manufacturer. Also, always follow the vehicle's regular maintenance schedule. And remember, while this pulley improves performance, drive safely and enjoy the smoother operation and faster response it brings.
