GSC P-D Chrome Polished Exhaust Valve - 30.5mm Head (STD) - Evo 1-9 / 90-98 DSM (Set 8) vendor_King Engine Bearings Important Notes:

Important Notes:

Most aftermarket Subaru exhaust systems need a 3 inch

especially under extreme driving conditions

2004-2021 Subaru WRX STi

which gives them about 1000% (that's ten times) better fatigue strength than those studs that are threaded prior to heat-treat (a very common industry practice)

GSC P-D Chrome Polished Exhaust Valve - 30.5mm Head (STD) - Evo 1-9 / 90-98 DSM (Set 8) vendor_King Engine Bearings Important Notes:Part #: 2001 8 When designing these valves, GSC used advanced 3D design and simulation programs to create a stronger and higher flowing valve head design. Prototypes were used in the specific applications to make sure that they have the highest flowing valve head that is available on the market today. The materials they have used have less valve distortion at the face than any of the tested designs which allow for better sealing under extreme