Engines and Components› Camshafts and Valvetrain

Cosworth

S2 Camshaft for Subaru EJ257 2.5L AVCS

$91,250.00

SKU: KK3766

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Special Order
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$100 Minimum Order
30 Days Return
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Description

The Cosworth KK3766 is a high-performance camshaft set specifically engineered for the Subaru WRX STI EJ25 (2.5L) engine, featuring AVCS (Advanced Active-System) compatibility. This S2 grind camshaft is designed to optimize mid to high RPM power delivery, making it an ideal upgrade for enthusiasts seeking enhanced engine performance. Each camshaft in the KK3766 set is ground from a new chill cast billet and finished using the same meticulous procedures employed in Cosworth's extreme-level race engines. The specifications for this set include an intake duration of 278 degrees with a lift of 10.65mm, and an exhaust duration of 274 degrees with a lift of 10.28mm. These parameters are tailored for the North American specification EJ257 engine, providing a noticeable increase in horsepower and torque where it matters most. As a direct replacement for the factory camshafts, the KK3766 set ensures a straightforward installation process for those familiar with engine component replacement.

Product descriptions are provided by our supplier partners and may not always be perfectly accurate. Not sure this fits? or call (760) 282-4645 and we’ll verify before you order.

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Specifications

BrandCosworth
Part NumberKK3766
CategoryEngines and Components
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Returns & Fitment

Built for enthusiasts. Every order is backed by our 30 day return window on eligible items. Unused and uninstalled products may be returned with approved RMA and no restocking fees when received in new condition. Orders placed through the MOTORMIA app with a complete build qualify for our Fitment Guarantee — free return shipping if the part doesn’t fit your exact setup. The guarantee covers fit only; installation must follow manufacturer instructions, and we recommend a qualified shop for parts marked Difficulty 4–5.

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Shipping

Orders are processed in 1–3 business days. In stock parts ship promptly from our partner network. Special-order items either aren’t currently stocked or are built to your spec — expect 4–6 weeks. If a part goes on backorder while your order is in the queue, we’ll reach out and work through discounted alternatives together.

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