GSC Power Division Billet S3 Camshaft Kit EJ205 280/280 Subaru WRX 2002-2005 | 7020S3

Overview

The GSC Power Division Billet S3 Camshaft Kit (Part #7020S3) is a high-performance, CNC-machined billet camshaft set engineered specifically for the 2002–2005 Subaru WRX EJ205 engine. Designed for serious motorsport enthusiasts and track-day competitors seeking maximum power gains, these 280/280 duration cams deliver aggressive lift and timing profiles that push the EJ205 well beyond factory limits. If you're building a purpose-driven street or competition WRX, the GSC S3 Billet Cams are the definitive upgrade for top-end power and sustained high-RPM performance.

Key Features & Benefits

• Billet Steel Construction — CNC-machined from premium billet steel for superior strength, durability, and dimensional accuracy compared to cast OEM camshafts, ensuring consistent performance under extreme cylinder pressures and heat.
• 280/280 Duration Profile — Aggressive 280-degree intake and exhaust duration maximizes high-RPM airflow and power output, ideal for forced-induction EJ205 builds targeting peak horsepower on the track or dyno.
• S3 Competition Grind — GSC's S3 specification represents their highest-performance street/race profile, engineered for modified engines running upgraded valve springs, head work, and supporting fuel/engine management upgrades.
• Precision CNC Machining — Tight manufacturing tolerances ensure perfect lobe geometry and journal sizing, resulting in smooth operation, reduced valvetrain wear, and predictable, repeatable power delivery.
• Direct OEM Replacement Fitment — Engineered as a drop-in replacement for the EJ205 cylinder heads, retaining factory cam gear bolt patterns for straightforward installation with no additional machining required.
• Optimized for Forced Induction — The S3 profile is specifically tuned to complement turbocharged EJ205 builds, synergizing with upgraded turbochargers, intercoolers, and fueling systems for maximum boost utilization.
• Matched Intake & Exhaust Set — Sold as a complete camshaft kit (both intake and exhaust cams included), ensuring a properly balanced and synchronized valvetrain for optimal scavenging and cylinder filling.

What's Included

• 1x GSC Billet S3 Intake Camshaft (280° Duration)
• 1x GSC Billet S3 Exhaust Camshaft (280° Duration)

Specifications

Fitment & Compatibility

The GSC Billet S3 Camshaft Kit (7020S3) is designed to fit the following vehicles:

• 2002–2005 Subaru WRX — EJ205 Engine (2.0L Turbocharged DOHC)

These camshafts are compatible with the EJ205 DOHC cylinder head configuration. Always verify your engine code and head casting prior to installation. These cams are intended for modified, built engines and are best suited for applications running upgraded valve springs (GSC or equivalent), aftermarket engine management (e.g., Cobb Accessport, AEM EMS), and supporting fuel system upgrades. Cross-reference OEM camshaft part numbers for your specific build before purchasing.

Installation

The GSC S3 Billet Camshafts are designed as a direct replacement for the OEM EJ205 camshafts and retain factory cam gear bolt patterns. However, due to the aggressive S3 grind profile, professional installation by an experienced engine builder or performance shop is strongly recommended. Proper installation requires camshaft timing verification, valve clearance checking and adjustment (shimming), and ECU re-tuning to take full advantage of the S3 profile. Upgraded valve springs rated for high-lift performance camshafts are required when running the S3 specification — do not install on a stock valvetrain. A professional dyno tune is essential after installation to ensure safe and optimal performance.