GFB Under-Driven Crank Pulley for Subaru WRX/ STi (2014) MANLEYPISTONSEJ205 Aftermarket exhaust systems are often

Aftermarket exhaust systems are often of a larger tubing diameter than factory systems and as a result

• Stock FMIC Dyno Pull = 15 degree temp rise

• Ideal for high-end synthetic motor oil

It may be necessary to rotate your throttle body 180° for proper cable clearance

GFB Under-Driven Crank Pulley for Subaru WRX/ STi (2014) MANLEYPISTONSEJ205 Aftermarket exhaust systems are oftenThe Go Fast Bits 3 piece underdrive pulley kit includes crank, alternator, and power steering pulleys, along with the required belt. Crafted from aircraft grade 6061 T6 aluminum, these lightweight pulleys reduce crankshaft weight, resulting in quicker acceleration and sharper throttle response, much like a lighter flywheel. This kit offers up to an 85% reduction in rotating inertia, making the engine feel more lively and eager to rev, without causing