GrimmSpeed V2 Bypass Valve - Red - 2004-2021 Subaru STI / 2002-2007 WRX PDM_brand-merchandise Reduces trailing arm movement under

Reduces trailing arm movement under acceleration and braking loads

or 06-08 Forester

Features the new Grip Dynamics system which improves grip for better handling and performance by focusing on key alignment and dynamic handling elements

The inner and outer bushings at the front mount of this arm share the loads imposed by the rear suspension

GrimmSpeed V2 Bypass Valve - Red - 2004-2021 Subaru STI / 2002-2007 WRX PDM_brand-merchandise Reduces trailing arm movement underGrimmSpeed V2 Bypass Valve (Red) , 2004 2021 Subaru STI 2002 2007 WRX The GrimmSpeed V2 Bypass Valve in red for the 2004 2021 Subaru STI 2002 2007 WRX replaces the factory recirculating bypass valve with a performance unit that provides more consistent venting of boost pressure during throttle lift events. The factory bypass valve is adequate at stock boost levels but can become a limitation , or fail , as boost pressure increases with modifications.