GSC Power Division Billet S3 Camshaft Set Subaru WRX/STI EJ255/EJ257 Intake AVCS (GDA/GDB/GRB/GVB) 280° Billet

GSC Power-Division Billet S3 Camshaft Set - Subaru WRX/STI EJ255/EJ257 Intake AVCS (GDA/GDB/GRB/GVB) - 280° Billet

GSC Power-Division has built a strong reputation producing high quality billet camshafts for serious performance builds, and the S3 series represents their most aggressive street and competition grind. Designed for Subaru WRX and STI engines chasing serious power, these billet S3 cams are ground from solid billet material for superior strength and consistency over cast alternatives. With a target power band of 750–1000 WHP and a usable rev range of 4,500–9,500 RPM, these are purpose-built for high horsepower applications that demand reliable, repeatable valvetrain performance.

This listing covers the GSC Power-Division Billet S3 camshaft set for Subaru EJ255 and EJ257 engines fitted with intake-only AVCS. Compatible chassis include the GDA, GDB, GRB, and GVB platforms covering the WRX and STI model lines. This is a complete intake and exhaust camshaft set. Check product images for correct cam placement — long nose installs on the left side, short nose on the right.

Important: These camshafts require significant supporting modifications to realise their full potential. A built bottom end (sleeved or closed deck strongly recommended), built and ported heads with casting clearanced for the higher lift profile, and upgraded valve springs are all required. A standalone ECU or a speed density tune is strongly recommended to achieve proper idle characteristics. Head castings must be filed down slightly for lobe clearance — confirm this during installation. Must be fitted by an experienced engine builder. High zinc break-in oil is mandatory on flat tappet engines.

Specifications

• Intake — Advertised Duration: 280°, Duration @ 1.016mm (0.040 in): 240°, Peak Lift: 11.55mm, Centreline: 130°
• Exhaust — Advertised Duration: 280°, Duration @ 1.016mm (0.040 in): 241°, Peak Lift: 11.60mm, Centreline: 115°
• Material: Billet construction
• AVCS compatibility: Intake only
• Target power range: 750–1000 WHP
• Target rev range: 4,500–9,500 RPM
• SKU: 7025S3

Vehicle compatibility, fitment notes, and configuration details are provided in the tabs above. Please confirm your engine code, AVCS configuration, and chassis before ordering.

Not sure if these camshafts suit your build? Contact our team at sales@chicaneaustralia.com.au for expert advice.