GFB 13+ Subaru BRZ / 13+ Scion FR-S Lightweight Alternator Pulley

It might be hard to imagine how reducing the mass of a pulley makes a car go faster, but accelerating a heavy factory pulley from say 3000-7000 RPM in a second or two saps a measurable amount of torque. GFB Lightweight Pulleys reduce inertia by up to 85 percent, so most of the torque that used to accelerate the pulley can now be applied to the wheels. Subaru BRZ/86/FR-S Fitment: Scion FR-S Base 2013 to 2016 Subaru BRZ Limited 2013 to 2017 Subaru BRZ Premium 2013 to 2017 Subaru BRZ Series.Blue 2015 Subaru BRZ Series.HyperBlue 2016 Toyota 86 Base 2017