GSC High Pressure Conical Valve Spring Kit w/ Titanium Retainers & Chromoly Seats – Subaru EJ Turbo (GSC5073)
Engineered for Extreme RPM and Boost
The GSC Power-Division High Pressure Conical Valve Spring Kit is built for Subaru DOHC EJ Turbo platforms. This complete kit includes 16 high-pressure conical valve springs, 16 titanium retainers, and 16 chromoly spring seats—designed to handle aggressive cam profiles, elevated RPMs, and high boost levels with confidence.
Conical Design for Harmonic Control
Unlike traditional cylindrical or beehive springs, conical springs feature progressive coil spacing and diameter variation, acting as natural harmonic dampers. This reduces valvetrain shock, minimizes wear, and extends component life—especially critical in turbocharged engines pushed to their limits.
Advanced Surface & Heat Treatment
Each spring undergoes a super-finished surface process and a patented multi-step heat treatment to ensure consistent performance and long-term durability. Whether you're chasing 10,000 RPM or 50 psi of boost, this kit is built to keep your valvetrain stable and responsive.
Technical Specifications
| Setup | Coil Bind (in) | Install Height (in) | Seat Pressure (lbs) | Open Pressure @ 11.5mm Lift | Max Valve Lift (in) |
|---|---|---|---|---|---|
| HP Conical | 0.787 | 1.318 | 104 | 254 @ 0.866" | 0.455 |
Performance Limits
- Max RPM: 10,000 RPM
- Max Boost: 50 psi
Fitment Guide
- 2002–2005 Subaru WRX 2.0L Turbo DOHC (EJ205)
- 2004–2007 Subaru WRX STI 2.5L Turbo DOHC (EJ257)
- 2006–2014 Subaru WRX 2.5L Turbo DOHC (EJ255)
- 2008–2021 Subaru WRX STI 2.5L Turbo DOHC (EJ257)
- 2004–2006 Subaru Baja Turbo 2.5L DOHC (EJ255)
- 2005–2009 Subaru Legacy GT 2.5L Turbo DOHC (EJ255)
- 2005–2009 Subaru Outback XT 2.5L Turbo DOHC (EJ255)
- 1994–1998 Subaru Legacy Turbo 2.2L DOHC (EJ22T)
- 1992–1996 Subaru Impreza WRX 2.0L Turbo DOHC (EJ20G)
- 1996–2000 Subaru Impreza WRX STI 2.0L Turbo DOHC (EJ20K)
- 2001–2005 Subaru Impreza WRX STI JDM 2.0L Turbo DOHC (EJ207)
CA Residents: WARNING: Cancer and Reproductive Harm www.P65Warnings.ca.gov
