GSC Power Division 7026S1 Billet S1 Camshafts for 2008-2021 Subaru WRXSTI

Vehicle Fitment

• 2008-2021 Subaru WRX STI (EJ257 engine, Dual AVCS)

Features

• Full billet camshaft set (S1 profile) - precision ground for durability and consistency
• 264° advertised duration / 226° @ 0.040" (intake), 264° / 222° @ 0.040" (exhaust) - balanced for responsiveness and performance
• Peak valve lift: ~10.80 mm (intake), ~10.50 mm (exhaust) - increased airflow vs stock cams for better power potential
• Dual-AVCS compatible - retains variable valve timing functionality while improving performance headroom
• Suitable for stock or moderately upgraded turbo setups - supports builds up to ~500 WHP when paired with proper valve springs and tune
• Improved valve-train stability under boost or elevated RPM compared with cast OEM cams
• Forged billet construction - high strength and wear resistance under heavy use
• Drop-in fit - minimal machining required (minor cam-tower clearance check recommended before install)

Specifications

• Part Number: 7026S1
• Camshaft Set: 4 cams (intake & exhaust banks) for EJ257 dual-AVCS head
• Intake Duration (ADV): 264°
• Intake Duration @ 0.040": 226°
• Exhaust Duration (ADV): 264°
• Exhaust Duration @ 0.040": 222°
• Peak Valve Lift: 10.80 mm (intake), 10.50 mm (exhaust)
• Recommended Use: Stock-frame turbo or light/moderate upgrade (up to ~500 WHP)
• Valve Springs: Upgraded springs required (e.g., performance springs) for reliable operation

Included Components

• 1x Complete set of 4 GSC S1 Billet Camshafts (intake & exhaust) - 7026S1

Product Description

The GSC 7026S1 camshaft set delivers a well-balanced performance upgrade for 2008-2021 Subaru WRX STI (EJ257 Dual AVCS). With a 264° cam profile and ~10.8 mm/10.5 mm valve lift, these cams improve airflow and combustion potential over stock cams - giving stronger mid-range and top-end power while preserving usable low-end response. That balance makes them ideal for stock-frame or moderately built turbo setups, especially for enthusiasts targeting up to ~500 WHP with supporting modifications and tuning.

Manufactured from billet steel and precision-ground, the 7026S1 offers enhanced durability and valve-train stability under boost or during aggressive driving. The set retains Dual AVCS functionality, allowing you to keep variable valve timing benefits while adding headroom for power. Installation is mostly bolt-on for compatible EJ257 heads, though a clearance check (or minor filing on head castings) is recommended due to larger lobe dimensions. With upgraded valve springs installed, the 7026S1 is a strong foundation for a reliable mid-power STI build - combining improved performance, reliability, and OEM-plus drivability.