Cobb 08-21 Subaru STi Fuel Pressure Regulator Kit - 315200

The COBB Fuel Pressure Regulator Kit (Part #315200) is a purpose-built fuel system upgrade designed specifically for the 2008–2021 Subaru WRX STI. Engineered by COBB Tuning — one of the most respected names in Subaru performance — this kit delivers a straightforward, plug-and-play path to improved fuel pressure management for street-driven builds and tuned STIs pushing beyond stock fueling limits. Whether you're adding power through a COBB Stage package or building a comprehensive fuel system upgrade, the 315200 is a foundational piece that pairs naturally with complementary COBB fuel system components.

Key Features & Benefits

• Plug-and-Play Installation: The COBB FPR Kit is designed to install without cutting any factory hoses, keeping your build clean and reversible if needed. This dramatically reduces install complexity and the risk of errors during the process.
• Simple and Easy to Install: COBB designed this kit with the enthusiast installer in mind. Dedicated installation instructions (document #315200) are available directly through COBB's support portal, walking you through every step of the process for the GR/GV-chassis STI.
• Designed for the 2008–2021 STI Platform: This kit is application-specific, meaning every component is sized and configured for the EJ257-powered STI's fuel system — no universal adapters or guesswork required.
• Pairs with COBB's Fuel System Ecosystem: The 315200 kit is part of COBB's broader STI fuel system lineup, which includes the COBB Fuel Rails (343150), Fuel Rail Line Kit (343250), High Flow Fuel Pump (315400), and Fuel Pressure Sensor Kit (315650). Building around a single ecosystem ensures compatibility and simplifies tuning.
• Supports Proper Fuel Pressure Management: Upgrading the fuel pressure regulator is a key step when modifying fueling on a tuned STI, helping to ensure consistent fuel delivery under elevated demand — critical for safe, reliable power on a modified engine.

Specifications

• Part Number: 315200
• Brand: COBB Tuning
• Application: 2008–2021 Subaru WRX STI
• Installation Type: Plug-and-play; no cutting of factory hoses required
• Installation Documentation: Available via COBB's official support portal (cobbtuning.atlassian.net)

Fitment

The COBB Fuel Pressure Regulator Kit #315200 fits the 2008–2021 Subaru WRX STI. This covers the GR-chassis (2008–2014) and GV-chassis (2011–2014 sedan) STI models as well as the VA-chassis STI (2015–2021), all powered by the EJ257 engine.

Note: This is the complete FPR kit (315200). COBB also offers a standalone fuel pressure regulator (part #315250) intended for use with their Fuel Rail Kit — that is a separate product. Verify your specific build requirements before ordering. This kit does not appear to be listed for the WRX (non-STI) or any non-Subaru applications. If you are unsure whether this fits your specific trim or build configuration, contact ThreePiece.us before purchasing.

Why Buy from ThreePiece.us

ThreePiece.us ships the COBB 315200 Fuel Pressure Regulator Kit with free shipping on every order — no minimum required. Need to spread out the cost of your fuel system build? Affirm financing is available at checkout, so you can get the parts you need now and pay over time. Have a fitment question or want to confirm compatibility with your specific STI build or other COBB components? Our team is here to help — reach out before you order and we'll make sure you're getting exactly the right parts for your application.

Frequently Asked Questions

Does this kit require cutting the factory fuel hoses?

No. The COBB Fuel Pressure Regulator Kit is specifically designed as a plug-and-play solution that requires no cutting of factory hoses, making installation cleaner and more straightforward.

What years and models does part #315200 fit?

This kit is designed for the 2008–2021 Subaru WRX STI. It does not appear to be intended for the standard WRX or other Subaru models. If your vehicle falls outside this range, contact us to confirm compatibility.

Is this the same as COBB part #315250?

No — these are two different products. The 315200 is the complete Fuel Pressure Regulator Kit, while the 315250 is a standalone fuel pressure regulator designed specifically for use with the COBB Fuel Rail Kit. Make sure you're ordering the correct part for your application.

Are installation instructions available for this kit?

Yes. COBB provides dedicated installation instructions for the 315200 kit through their official customer support portal. The documentation is listed under COBB Product Install Instructions for Subaru Vehicles and covers the full installation process for the 2008+ STI.