• S1 billet camshaft, 268/266 duration
• Built specifically for EJ20 JDM/Euro Spec STI (not compatible with USA spec engines)
• Billet core for precision and consistency
• Genuine GSC Power Division engineering

S1: A mild, street-friendly upgrade over stock

GSC's S1 billet camshaft is ground to 268/266 duration specifically for the EJ20 JDM/Euro Spec STI platform, positioned within GSC's cam lineup as a mild, street-friendly upgrade over stock. Being a billet cam rather than a re-ground factory core, this camshaft starts from a precision blank rather than being limited by the factory core's base circle and material properties. That billet construction is what lets GSC achieve consistent, repeatable lobe profiles across every cam they produce. That's the kind of detail that separates genuine engineering from a basic replacement part.

What This Cam Actually Feels Like to Drive

In terms of real-world feel, this cam delivers smooth idle quality and broad, usable power across the whole rev range, giving you a clear expectation of how the car will behave before you commit to the install. GSC's cam lineup is specifically staged this way so you can choose the level of aggressiveness that matches your actual build and driving style, rather than guessing at a generic "stage" cam from another brand. This variant is JDM/Euro spec specific and will not work correctly on a USA spec engine, so confirm your exact engine specification before ordering. It's a small distinction that makes a real difference once you're actually building the engine.

Straight From Subispeed

A billet S1 cam for 2002-2014 WRX / 2004-2014 STI — a mild, street-friendly upgrade over stock, with genuine GSC engineering behind the lobe profile.

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