GSC Power-Division intake valves for the EJ WRX and STi models. Intake valves are sold as a set of 8 or individually as needed. Available in the standard 36mm size or +1mm oversized. Valve stem diameter is 6.0mm, overall length is 104.40mm.
Vehicle Fitment:
Subaru EJ20/EJ25
2002-2014 Subaru WRX
2004-2021 Subaru STi
GSC Intake Valves:
| Part Number: | Head Diameter Size: | Material: | Quantity: |
| GSC 2012-8 | STD Size (36mm) | 21-4N | Set of 8 |
| GSC 2012-01 | STD Size (36mm) | 21-4N | Single Valve |
| GSC 2014-8 | +1mm (37mm) | 21-4N | Set of 8 |
| GSC 2014-01 | +1mm (37mm) | 21-4N | Single Valve |
More Info:
Using advanced 3D design and simulation software, GSC has created a stronger and higher flowing valve head design. GSC flow tests prototype valve heads in the specific applications to ensure the highest flowing valve head available on the market today. With the materials used, GSC offers less valve distortion at the face than any of the tested designs. Less distortion allows for better sealing under extreme conditions and more consistent performance throughout the life of the valve.
- 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 micro polished to allow for less oil retention on the stem, which creates less drag on the stem to guide for a smoother motion
- Intake valves are a modified 21-4n stainless and exhausts are a modified 23-8n stainless material for high heat capacity while maintaining longevity
- Valve tips are either hardened or have a stelite wafer tip fused so that the tip is within 5 Rockwell C of the rocker or valve tappet for extended life and less wear
- Valve tip lengths – GSC takes extra time to adjust tip heights on the applications to require less tipping of the valve, to maintain proper tip height for proper valve train geometry, and to cut down on install times when setting valve lash
- GSC has also adjusted the keeper groove to properly balance intake and exhaust spring pressures to reduce the use of valve spring shims and maximize performance from GSC spring and retainer kits
- Valves will work with an OEM keeper/lock or, when available, GSC upgraded keeper/lock. It is not mandatory, but it is suggested, that any valve lock not be reused on performance applications due to material grooving
Pictured:
Photos are for reference.
