The COBB Tuning GESi Catted 3″ Downpipe begins with a CAD designed cast bellmouth that smoothly blends air exiting the turbocharger’s turbine housing. Minimizing turbulence when exhaust gasses from the wastegate join into those flowing through the turbine helps to prevent excessive back-pressure. The cast housing is capped off with a COBB logo and auxiliary O2 bung for those wanting to install a wideband sensor early in the exhaust path.
A welded bracket utilizes the factory hard mount near the transmission reducing stress on the turbocharger mounting bolts and studs.
Corrosion resistant and mandrel bent 3″ 304 Stainless Steel tubing carries exhaust gasses down stream into a COBB-exclusive GESi 300 cell high flow catalytic converter. A second O2 bung is located directly after the catalytic converter and is to be used by the OEM Rear O2 sensor.
A CAD designed, cast 304 stainless steel, flange finishes off the tail section of the downpipe. The reinforced cast flange is less susceptible to warp during assembly and for those of you installing with the strength of Hulk. A stainless adapter flange and included MLS gasket allows direct fit with the factory exhaust or COBB Cat-Back Exhaust utilizing the OEM donut gasket. Included COBB proprietary shoulder nuts allow installation of the factory spring bolts without fuss.
Subaru GESi Catted 3″ Downpipe WRX/STi 2002-2007, Forester XT 2004-2008
- CAD Designed Cast Turbo Outlet for Maximum Flow
- 304 Stainless Steel for Corrosion Resistance
- High Flow GESi Catalytic Converter
- Two O2 Bungs for Factory & Aftermarket Sensors
- Included Adapter Utilizes Stock Donut Gasket for Optimal Sealing & Long Life
This downpipe requires tuning changes. COBB offers OTS Map support for some vehicles, check maps available for your car here: MAPS. No OTS Maps available? Find and contact your local Protuner here: PROTUNERS.
This part is in the process of external testing with the EO process ongoing.
NOT LEGAL FOR SALE OR USE IN CALIFORNIA ON ANY EMISSION CONTROLLED MOTOR VEHICLE.
While we believe that these parts comply with EPA’s Anti-Tampering Policy we have not completed the testing/CARB EO submission process.