GFB – Pulley Kit – Subaru EJ20 EJ25

SKU: 2856
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Upgrade your driving experience with the GFB lightweight under-drive pulley kit, delivering enhanced throttle response and increased power. Crafted from premium 6061-T6 aluminum billet, GFB’s pulleys are significantly lighter than factory steel counterparts, optimizing engine acceleration with an average weight reduction of 2kg (7kg for GFB 300ZX pulley). The innovative design incorporates under-driving, reducing accessories’ load at high RPM for additional power gains. Pair it with the Atomic Boost Controller for substantial power increases, as demonstrated in the MY01-02 Subaru WRX, without exceeding the factory peak boost level. GFB also offers a discreet Subaru crank pulley, non under-drive style, seamlessly blending with the stock item while providing a substantial weight reduction. Elevate your driving performance with GFB?precision engineering for enthusiasts. Available in Black for all Subaru EJ type engines. Unlock power and responsiveness effortlessly!

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Enhance your driving experience with the GFB lightweight under-drive pulley kit, designed to optimize throttle response and boost power effortlessly! Crafted from high-grade 6061-T6 aluminum billet using state-of-the-art Multi-Axis CNC machines, GFB’s pulleys are significantly lighter than their factory steel counterparts, resulting in an average weight reduction of around 2kg (7kg for the GFB 300ZX pulley). This reduction in weight drastically minimizes rotating inertia, facilitating faster engine acceleration?especially noticeable in the lower RPM range before the turbo spools up, akin to the effect of a lightened flywheel.

The innovative design goes beyond weight reduction by incorporating under-driving. By making the crank pulley smaller, GFB slows down accessories and reduces the driven load at high RPM, unlocking additional power increases. This under-driving technique doesn’t compromise accessory efficiency between idle and 1400RPM, ensuring optimal functionality for battery charging and power steering. As RPMs increase, the under-driving proportionally reduces wasted power, resulting in substantial power gains without increasing boost.

Experience the remarkable impact of the Atomic Boost Controller on your MY01-02 Subaru WRX, especially when paired with a turbo-back exhaust. Tested against the factory controller, the Atomic Boost Controller demonstrated a significant increase in power, providing as much as 18kW (23.4hp) at the wheels in the lower rev range. The boost rises earlier than the factory controller, delivering better acceleration from 1700RPM earlier in the rev range?all without surpassing the factory peak boost level. Notably, the MY01-02 WRX benefits exceptionally from this modification, as the factory boost mapping is conservative to maintain a flat torque curve and linear power delivery.

For MY01-02 WRX enthusiasts seeking an impactful yet subtle modification, consider the Subaru crank pulley, non under-drive style, by GFB. Made from 6061 alloy, this pulley weighs a mere 550g, as opposed to the hefty 2180g of the factory WRX unit (2575g for the STi model). After installation, it seamlessly blends with the stock item, providing both performance and aesthetics. Elevate your driving experience with GFB?your trusted choice for quality and performance.

Note: The Subaru crank pulley is available in Black only and is compatible with all Subaru EJ type engines, including EJ20 and EJ25. Upgrade your driving experience with the best “bang-for-your-buck” modification available!


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