Air and Fuel› Fuel Injection Systems and Components - Electronic

COBB Tuning

EJ257 High-Volume Fuel Rails

$300.00

SKU: COBB343150

Special Order
Special Order
Ships in 4–6 weeks
Free Shipping over $200
$100 Minimum Order
30 Days Return
INSTALL DIFFICULTY
DIY PRO SHOP

Moderate — 2–4 hours

Overview

The COBB Tuning Fuel Rails are upgraded fuel rails designed for high-flow EJ257 builds in the 2008-2021 Subaru WRX STI. These rails feature a larger internal volume than factory units to reduce pressure drop between the regulator and injectors under high demand. They ensure more consistent fuel pressure distribution across all four injectors.
Show original supplier description
The COBB Tuning Fuel Rails are engineered for performance-driven 2008-2021 Subaru WRX STI models equipped with the EJ257 engine. These upgraded fuel rails are crucial for high-flow builds that utilize larger turbochargers, higher boost pressures, and increased injector duty cycles. By increasing the internal volume beyond that of the factory rails, they effectively minimize fuel pressure drops, ensuring consistent delivery to each injector even under extreme demand. This enhanced fuel distribution is vital for maintaining optimal performance and preventing fuel starvation in modified engines. The larger volume provides more consistent pressure distribution between injectors, significantly reducing the variation that can occur with stock components when operating at high flow rates. The rails are constructed with an anodized black finish and feature a -6AN inlet size, suitable for top-feed injectors. All necessary hardware and fittings are included for a complete installation. COBB Tuning has a long-standing reputation for developing performance software and hardware for turbocharged enthusiast vehicles. The RallySport Take highlights that these fuel rails are essential for high-flow EJ257 builds, improving injector-to-injector consistency.

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.

Fitment

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Specifications

BrandCOBB Tuning
Part NumberCOBB343150
CategoryAir and Fuel
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(760) 282-4645 hello@motormia.co

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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.

Free shipping over $200 in the continental US. Alaska, Hawaii, U.S. territories (Puerto Rico, U.S. Virgin Islands, Guam, American Samoa, and the Northern Mariana Islands), and international orders carry surcharges — most appear at checkout. Some exceptions (LTL freight, or suppliers who quote freight only after we place the order) won’t. In those cases we’ll reach out with the exact charge before your order moves forward.

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