GSC Power Division 37mm (+1mm) Intake Valves (Set of 8) Subaru 2002-2014 WRX / 2004-2020 STI

GSC set out to create the best performance, longest lasting Subaru oversize (+1) 37mm intake valves available to the aftermarket. Using advanced 3D design and simulation programs GSC created a stronger and higher flowing valve head design. GSC flow tests prototype valve heads to specific applications, making sure they have the highest flowing valve head available on the market today. The materials used by GSC have less valve distortion at the face than any of the tested designs. Less distortion allows better sealing under extreme conditions and more consistent performance thru the life of the valve.  Valve Features: +1mm Oversize 37mm intake valves Swirl polished heads for smoother air flow over the valve Back cut to reduce valve weight for higher rpm, higher boost pressure and allow for more aggressive cam profiles without increasing valve spring seat pressures. Valve stems are micropolished to allow for less oil retention on the stem which creates less drag on the stem to guide for