Cobb 08-21 Subaru STi Fuel Pressure Regulator Kit-COBB-COBB315200
Cobb 08-21 Subaru STi Fuel Pressure Regulator Kit-COBB-COBB315200
Cobb 08-21 Subaru STi Fuel Pressure Regulator Kit-COBB-COBB315200
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Cobb 08-21 Subaru STi Fuel Pressure Regulator Kit

COBB
COBB315200
700424673650
Fuel Pressure Regulators
20+ Units In Stock - Ships Next Business Day
$ 410.00
$ 410.00

SKU: B315200   |   UPC: 700424673650

COBB Adjustable Fuel Pressure Regulator Kit – 2008-2021 Subaru STI & 2008-2014 WRX

The COBB 315200 replaces the factory regulator with a billet aluminum Aeromotive unit on 2008-2021 Subaru STI (EJ257) and 2008-2014 WRX (EJ255) for precise fuel delivery. Adjust base pressure from 30-70 psi with true 1:1 manifold reference to eliminate droop under boost, supporting E85, flex fuel, large injectors, and upgraded pumps. Kit includes firewall bracket, braided stainless line, and all fittings for direct bolt-on installation.

Key Features

  • Aeromotive 13129 Regulator: True 1:1 rising rate maintains fuel pressure psi-for-psi with manifold pressure across 30-70 psi range for consistent fueling on high-power setups.
  • CNC Billet Firewall Bracket: Black anodized 6061 aluminum ensures secure mounting with perfect OEM-like fitment on STI and WRX firewalls.
  • Braided Stainless -6 AN Line: Pre-assembled PTFE-lined line with fittings delivers reliable flow without leaks or restrictions.
  • Full 1:1 Manifold Reference: Prevents pressure drop during boost for stable AFRs on stock or aftermarket fuel systems.
  • Made in the USA: Aeromotive regulator and COBB components backed by lifetime warranty against defects.

Product Notes

  • Fits all 2008-2021 STI (EJ257) and 2008-2014 WRX (EJ255) with stock or aftermarket fuel rails and pumps.
  • Accessport tuning required after pressure adjustments to match fuel maps.
  • In stock - ships same or next business day via UPS/FedEx Ground.

Installation Notes

  • Professional installation recommended.
  • 45-60 minute install: Mount firewall bracket, route braided line, replace factory regulator.
  • Full color instructions and all hardware included; compatible with stock lines.

This Part Fits

Year Make Model Submodel
2008-2021 Subaru WRX STI Base
2008-2021 Subaru WRX STI Limited
2015 Subaru WRX STI Launch Edition
2008-2014 Subaru Impreza WRX STI Base
2011-2014 Subaru Impreza WRX STI Limited
2010 Subaru Impreza WRX STI Special Edition
2008-2014 Subaru Impreza WRX Base

Why Choose COBB Tuning?

  • #1 selling adjustable FPR for EJ25 Subaru models over 20 years.
  • Engineered and manufactured in the USA for direct fitment.
  • Proven on 600-1000+ hp EJ builds worldwide with Aeromotive integration.

Frequently Asked Questions

  • Q: Will this work on 2015+ WRX FA20?
    A: No, use COBB 315250 kit for FA20 WRX STI; this is EJ25-specific.
  • Q: What materials are used in construction?
    A: Billet 6061 aluminum bracket (black anodized), Aeromotive regulator body, and PTFE-lined braided stainless steel line.
  • Q: What warranty and tuning is needed?
    A: Lifetime against defects; Accessport tuning required post-install for pressure changes.

Shipping & Handling

  • Method: UPS/FedEx Ground
  • Availability: In stock - ships same or next business day
  • Packaging: Official COBB retail box, 10" x 8" x 4"
  • Weight: 1.9 lbs

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