Product Specifications
Subaru WRX and WRX STI GT35 / GT35R 3-Inch Catless Downpipe
Built for Subaru WRX EJ255 and WRX STI EJ257 turbo-upgrade projects, this Flashark catless downpipe replaces the exhaust section after a Garrett GT35 or GT35R turbocharger with a T3 turbine housing. Its 3-inch path connects the upgraded turbo to a compatible exhaust system.
T-304 stainless steel tubing, mandrel bends, a CNC-machined T3 flange and TIG-welded joints support a durable connection for this configuration.
Specifications
| Specification | Details |
|---|---|
| Part type | Catless turbo downpipe |
| Diameter | 3 inches |
| Material | T-304 stainless steel |
| Construction | Mandrel-bent tubing; TIG-welded joints |
| Turbo connection | CNC-machined T3 flange for the stated GT35 / GT35R configuration |
| O2 sensor provision | One M18×1.5 bung with plug |
Key Features
- GT35 / GT35R-specific connection: Designed around a Garrett GT35 or GT35R turbocharger with a T3 turbine housing.
- Full 3-inch path: Supports connection to a compatible 3-inch cat-back without a neck-down section.
- T-304 stainless construction: Provides the heat and corrosion resistance described for this performance build.
- Mandrel bends and TIG-welded joints: Form the exhaust path between the upgraded turbo and the downstream system.
- O2 sensor bung: Provides the stated M18×1.5 sensor location with a plug.
- Installation hardware: The listed gaskets, bolts and nuts support the stated connections.
What Is Included
- 1 × Flashark GT35 / GT35R 3-inch stainless downpipe
- 1 × turbo outlet gasket
- 1 × downpipe-to-exhaust gasket
- 1 × M18×1.5 O2 sensor bung with plug
- 1 × hardware kit with bolts and nuts
Check Before Ordering
- This downpipe does not fit a stock VF-series or TD04 turbocharger or a stock turbo exhaust layout. Confirm the GT35 / GT35R T3 turbine housing, outlet flange and downstream connection on your build.
- A standard Subaru Impreza 2.0L or 2.5L designation alone does not establish fitment. Confirm the WRX EJ255 or WRX STI EJ257 application and turbo conversion.
- The outlet is intended for a compatible 3-inch cat-back. A 2.5-inch exhaust may require an adapter or exhaust upgrade.
- This is a catless configuration. ECU tuning is required after installation. Intended for off-road or track use only; check local emissions regulations before purchase.
- The selectable header and cat-back options change the items ordered. Check the selected variant before checkout; the included-items list above describes the downpipe itself.
What Does This Downpipe Do?
The downpipe is the exhaust section between the turbocharger's turbine wheel and the rest of the exhaust system. The factory EJ257 downpipe is 2.5 inches with a restrictive catalytic converter—it's the single biggest exhaust bottleneck on a GT35-powered build.
By replacing it with this full 3-inch downpipe, backpressure drops significantly, the turbo spools faster and holds boost longer, exhaust gas temperature drops, and mid-range torque improves. Power gains: 150–200 WHP over stock (GT35 + downpipe + proper tune).
Shipping & Returns
Free U.S. Shipping: Orders are typically processed within 1–2 business days and delivered within 7–9 business days. Additional charges may apply to remote areas.
30-Day Returns: Unopened and unused items in their original packaging may be returned within 30 days of receipt. Return shipping is covered for verified quality issues.
Worry-Free Delivery: Optional protection against eligible loss, theft, delay, or transit damage is available at checkout.
