Turbo XS 02-07 WRX-STi / 04-08 Forester XT High Flow Catted Downpipe - WS02-DPC

The Turbo XS High Flow Catted Downpipe (WS02-DPC) is a purpose-built performance exhaust upgrade engineered specifically for the 2002–2007 Subaru WRX/STI and 2004–2008 Subaru Forester XT. For EJ-platform Subaru enthusiasts looking to reduce exhaust backpressure and unlock more of their turbocharged engine's potential, this catted downpipe represents one of the most impactful bolt-on upgrades available — all while retaining a high-flow catalytic converter for emissions-conscious builds.

Key Features & Benefits

• Massive Cast 304 Stainless Steel Bellmouth: The downpipe opens with a large cast 304 stainless steel bellmouth at the turbine outlet, dramatically improving exhaust gas exit velocity and reducing the turbulence that kills response on stock units. Stainless construction resists corrosion and heat fatigue for long-term durability under demanding boost conditions.
• 3-Inch Diameter Piping: The bellmouth tapers into genuine 3.0-inch piping — a meaningful step up over the restrictive factory downpipe — allowing spent exhaust gases to evacuate the turbocharger more freely. Less backpressure means faster spool, improved throttle response, and more power potential when paired with a proper tune.
• High-Flow Catalytic Converter Included: Unlike a catless downpipe, the WS02-DPC retains a high-flow catalytic converter. This makes it a practical choice for daily-driven WRX, STI, and Forester XT builds where retaining some emissions hardware is desirable — while still flowing far better than the OEM catalytic unit.
• Made in the U.S.A.: This Turbo XS downpipe is a domestically manufactured part, which is a meaningful quality assurance point for buyers comparing import-quality alternatives.
• Direct Bolt-On Fitment: Designed specifically for the 2002–2007 Impreza WRX/STI and 2004–2008 Forester XT chassis, this downpipe is engineered to bolt directly to the factory turbocharger outlet and connect to the OEM or aftermarket cat-back exhaust without fabrication.
• Reduced Exhaust Backpressure: By replacing the highly restrictive OEM downpipe and its small-capacity catalytic converter, the WS02-DPC reduces the primary source of exhaust restriction on these turbocharged EJ engines — a critical benefit for anyone seeking to maximize performance from supporting modifications like intake, intercooler, or an ECU tune.

Specifications

• Brand: Turbo XS
• Part Number: WS02-DPC
• SKU: TXSWS02-DPC
• Material: Cast 304 Stainless Steel bellmouth; 3.0-inch stainless steel piping
• Catalytic Converter: High-flow cat included
• Country of Manufacture: Made in the U.S.A.
• CARB Status: NOT CARB legal — not for sale or use in California

Fitment

The Turbo XS WS02-DPC downpipe fits the following Subaru vehicles:

• 2002–2007 Subaru Impreza WRX
• 2006–2007 Subaru Impreza WRX Limited
• 2004–2007 Subaru Impreza WRX STI
• 2007 Subaru Impreza WRX STI Limited
• 2006–2007 Subaru Impreza WRX TR
• 2004–2005 Subaru Forester XT
• 2005 Subaru Forester XT Premium
• 2006–2008 Subaru Forester XT Limited
• 2008 Subaru Forester Sports 2.5 XT

Does NOT fit: 2008–2014 Subaru WRX/STI (see the Turbo XS WS08-DPC for those applications), naturally aspirated Impreza models, or any non-turbocharged Forester trim. Important: This product is not legal for sale or use in California due to CARB regulations. Buyers in CA should verify local emissions laws before ordering.

What's in the Box

• Turbo XS High Flow Catted Downpipe (WS02-DPC) — complete assembly with high-flow catalytic converter integrated

Why Buy from ThreePiece.us

• Free Shipping on Every Order: Every order ships free — no minimum threshold to hit on this product.
• Affirm Financing Available: Split your purchase into manageable monthly payments through Affirm at checkout — ideal for higher-ticket performance upgrades like this downpipe.
• Fitment Expertise: Our team specializes in Subaru performance parts. If you have questions about whether this downpipe fits your specific WRX, STI, or Forester XT build — including trim level or model year edge cases — reach out before ordering and we'll confirm compatibility.
• Curated Performance Catalog: We stock complementary Turbo XS components like the WS02-CP high-flow cat pipe and WS02-SBE Stealth Back Exhaust, so you can build a cohesive exhaust system from a single trusted source.

Frequently Asked Questions

Is this downpipe legal in California?

No. The Turbo XS WS02-DPC is not CARB (California Air Resources Board) legal and is explicitly not for sale in California. Buyers in other states should still verify their local emissions testing requirements before purchasing any aftermarket downpipe.

Does the WS02-DPC include a catalytic converter, or is it catless?

This is the catted version — it includes a high-flow catalytic converter as part of the assembly. If you want the cat-pipe section only as a separate component, Turbo XS also offers the WS02-CP High Flow Catalytic Converter Pipe separately.

Will this fit my 2008 WRX or STI?

No. The WS02-DPC is designed for the 2002–2007 WRX/STI (GD/GG chassis). For 2008–2012 WRX/STI applications, Turbo XS makes the WS08-DPC, which is a separate product engineered for that generation.

Does this downpipe require a tune after installation?

While we cannot make specific tuning recommendations here, it is widely understood in the Subaru community that any significant exhaust modification — particularly a downpipe upgrade — has the potential to affect air-fuel ratios and boost control. We strongly recommend consulting with a qualified Subaru tuner to ensure your ECU is properly mapped after installation for safe and optimal performance.