SKU: 5076
GSC P-D Subaru EJ Series Conical Valve Spring and Ti Retainer Kit 2002-2021 WRX STI
The GSC P-D Subaru EJ Series Conical Valve Spring and Ti Retainer Kit delivers precise valvetrain control for EJ20 and EJ25 turbo engines in Subaru WRX STI Impreza Forester and Legacy models from 2002 to 2021. Conical springs cut valvetrain mass by 28 percent over stock while titanium retainers drop 4 grams per valve for reliable high RPM operation past 9000 RPM. This kit supports 500 plus wheel horsepower builds with dual valve springs maintaining 98 pounds seat pressure and 238 pounds open at 0.380 inch lift.
Key Features
- Conical Beehive Design: Progressive dual rate springs with 1.150 inch closed height reduce mass harmonics and resonance for smoother high RPM stability
- Titanium Retainers: Lightweight 10 gram Ti retainers machined with precise lock grooves ensure retention under 40 psi boost and 1.2mm lift cams
- High Pressure Ratings: 98 lbs closed at 1.150 inches 238 lbs open at 0.380 inches lift coil bind at 1.000 inches prevent dropped valves
- Chromoly Steel Springs: Heat treated premium wire 0.079 inch thick inner ID 0.510 inch outer OD 0.945 inch endure 1000 plus hours track abuse
- Complete Kit: 16 springs and 16 retainers direct OEM replacement boosts rev limit and power in turbo EJ applications
Product Notes
- Valve locks seats and spring seats sold separately verify compatibility with your setup
- Check installed spring height and retainer to guide clearance before full assembly
- Kit weighs 3.65 pounds ships in 10 x 6 x 4 inch box
Installation Notes
- Professional installation recommended.
- Measure installed height after valve job to confirm pressures match specs
- Compatible with stock heads aftermarket cams and GSC valve locks
This Part Fits
| Year | Make | Model | Submodel |
|---|---|---|---|
| 2002-2007 | Subaru | Impreza | WRX |
| 2008-2021 | Subaru | Impreza | WRX |
| 2015-2021 | Subaru | WRX | All |
| 2004-2021 | Subaru | Impreza | WRX STI |
| 2004-2013 | Subaru | Forester | XT |
| 2005-2009 | Subaru | Legacy | GT |
| 2005-2006 | Subaru | Saab 9-2X | Aero |
Why Choose GSC?
- Developed for record setting Subaru race cars in Formula Drift and rallycross
- CNC machined in USA with dyno tested springs for consistent performance
- Lifetime warranty against spring failure when properly installed
Frequently Asked Questions
- Q: Does this kit fit stock EJ257 heads on 2004-2021 STI?
A: Yes direct bolt on for all EJ20 EJ25 turbo heads including STI WRX and Legacy GT confirm no head machining interferes with retainer height - Q: What material are the springs and retainers?
A: Premium chromoly steel springs with super clean EDM cut ends titanium 6AL4V retainers both shot peened for fatigue resistance - Q: What warranty applies and install tips?
A: Lifetime on springs against sagging or breaking requires professional install with proper height check and matching locks
Shipping & Handling
- Method: UPS Ground
- Availability: In stock – ships same or next business day
- Packaging: Secure foam packed box 10 x 6 x 4 inches
- Weight: 3.65 pounds
Reviews
There are no reviews yet.