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SKU: B745670 | UPC: 700424680221
Cobb 15-18 Subaru WRX / 14-18 FXT LF By-Pass Valve
The Cobb LF Bypass Valve serves as a direct replacement for the factory plastic diverter valve on 2015-2018 Subaru WRX and 2014-2018 Forester XT models. Its low-force spring design ensures quick boost recovery and stock-like throttle response while handling up to 34 PSI. This upgrade delivers reliable compressor surge protection for daily driving and track use.
Key Features
- CNC Machined Aluminum Housing: Provides lightweight strength and corrosion resistance for long-term reliability.
- Reinforced Diaphragm: Built to withstand high boost pressures up to 34 PSI without failure.
- Low Force Spring: Delivers fast boost onset matching OEM feel on stock or low-boost setups.
- Direct Bolt-On Fit: Installs in the OEM location with no cutting or modifications needed.
- Complete Hardware Kit: Includes O-rings, fittings, and fasteners for plug-and-play assembly.
Product Notes
- Ideal for stock turbo configurations or mild modifications up to 25 PSI.
- Operate quietly compared to atmospheric vent styles.
Installation Notes
- Professional installation recommended.
- Remove OEM valve from turbo outlet pipe and throttle body hose in 30-45 minutes.
- Compatible with factory brackets and vacuum lines torque to spec.
This Part Fits
| Year | Make | Model | Submodel |
|---|---|---|---|
| 2015-2018 | Subaru | WRX | Base |
| 2015-2018 | Subaru | WRX | Premium |
| 2015-2018 | Subaru | WRX | Limited |
| 2014-2018 | Subaru | Forester | 2.0XT |
Why Choose Cobb?
- Over 20 years developing Subaru-specific tuning components.
- Manufactured in the USA with precision engineering.
- Supported by extensive dyno testing and customer resources.
Frequently Asked Questions
-
Q: Will this fit 2019-2021 WRX models?
A: Yes, Cobb confirms compatibility through 2021 VA-chassis WRX due to identical OEM valve design. -
Q: What materials are used in construction?
A: Billet CNC aluminum body with a durable reinforced rubber diaphragm and stainless hardware. -
Q: Does installation require ECU tuning?
A: No tuning needed it's a mechanical drop-in replacement for the OEM valve.
Shipping & Handling
- Method: UPS Ground or USPS Priority
- Availability: In stock - ships same or next business day
- Packaging: Compact box 6" x 4" x 3"
- Weight: 0.31 lbs
COBB
COBB Tuning parts for turbocharged performance platforms are stocked at Black Ops Auto Works. Shop the Accessport ECU programmer, cold air intakes, cat back exhaust systems, and supporting hardware engineered for Subaru WRX and STI, Ford Focus ST and RS, Ford F-150 EcoBoost, Mazdaspeed3 and 6, Nissan GT-R, Porsche, BMW, and Volkswagen platforms. Every product is filterable by year, make, model, and trim so the correct part ships the first time. Black Ops Auto Works carries 372 COBB SKUs across tuning, intake, and exhaust categories. What This Brand Covers COBB Tuning built its reputation on the Accessport, one of the most widely used ECU flash tools in the aftermarket, and has expanded into intakes, exhausts, downpipes, and supporting hardware for a range of turbocharged platforms. The catalog centers on a defined group of import and Euro performance vehicles rather than a single brand family. Brand Focus COBB Tuning parts are engineered primarily for Subaru, Ford, Mazda, Nissan...
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