COBB Tuning Downpipe Catted Bellmouth

Part #: COB 512202


Brand: COBB Tuning
Includes Catalytic Converter: Yes
Installation Hardware Included: No
Mouth Design: Bellmouth
Piping Coating: No
Piping Flex Joint: No
Piping ID: 3.00in
Piping Material: 304 Stainless Steel
Piping Taper: Yes
Catalytic Converter Cell Count: 200
Mfgr. Warranty: 1 Year
Return Policy:

RallySport Guarantee - 30 Days

Items that are covered under the RallySport Guarantee offer a 30 day no questions asked return policy.

RallySport Guarantee items may be returned within 30 days of the original invoice date and must include all the original parts and contents for a refund.

The RallySport Guarantee does not apply to products that have been modified, damaged, misused or abused. All returns require an RMA (Return Merchandise Authorization) Number, and freight charges are strictly non-refundable. For more information regarding our freight refund policy, please refer to our return policy page found HERE.
RallySport Guarantee


The COBB Tuning turbo downpipe is one of the premier modifications most owners look to upgrade on their vehicle. By opening the diameter of exhaust flow coming out of the turbo, this downpipe unleashes power where the stock restrictive unit lacks.

The COBB Tuning downpipe is available in a "Street" version that comes with a single high flow catalytic converter. A downpipe combined with the performance tuning found in the AccessPORT is the first step to any enthusiast looking to unlock the potential of their engine, while still maintaining a stock look around their vehicle.

The Cobb Down pipe utilizes the stock style donut gasket which allows for the use of stock or tapered catbacks.

Because this product replaces/removes an OEM emissions control device we must state that this product is for offroad use only.

Tapers to 2.5" stock flange

REVIEWS ( 28 )



get the gasket and save the shield bracket.
Ryan.mcgraw46599 12 months ago
Came in a really neat box. well wrapped. for sure you need the grimmspeed turbo to dp gasket. be aware doing this yourself, when you remove the heat shield, which is a pain, you need to KEEP the secondary bracket and re-attach it after to give the shield something to attach to. just fyi. need a protune desperately, but power increase from OTC map was insane.

Cobb Downpipe
Combomaster 1 year ago
All I can say is that's some beautiful craftsmanship. The car breaths so much better. I've been having way more fun driving my subaru on a daily basis.

COBB quality
guest55c8d82bcaae52f460a9c495 1 year ago
Very high quality, Pain in the butt to get the o2 sensor off the stop DP but other than that easy install, tremendous power gain with COBB AP, never regret buying COBB products.
Verified Purchase
Good Power Gain
Darkendays488471 1 year ago
Installed on a 04 WRX with a automatic transmission. Install took a few hours due to rusted hardware. I wrapped the down pipe with the titanium wrap. After install I tuned to stage 2 with my V3 access port. I was running stage 1 before hand and the power increase is very noticeable. There is also a increase in exhaust noise, I am running a stock exhaust with a no name welded on muffler. I did have a fitment issue with bolting the downpipe onto the waste gate studs, I needed to drill the mounting holes bigger by a millimeter otherwise it would not mate up with the studs. Its a bummer that cobb did not supply new hardware with a 600 dollar down pipe. Overall I am happy with the product. Make sure you get new gaskets when installing.
Verified Purchase
perfect fit but a check engine light is on
Lavjerj22942 2 years ago
Install was relatively easy (I do have lift access though) and the only trouble I had was two of the heat shield bolts broke on me. A disappointment I do have though is that since this gets rid of the main catalytic converter you will probably get a check engine light for catalyst inefficiency. They did say that if i bought the Cobb programmer it would fix this but i don't have that to verify that.


  • AnswerQ: 07 WRX TR AP stage 2 requirement?  MattSax07WRXTR 5 months ago

    Is this all I need to reflash to Cobb AP stage 2? I like my stock exhaust.

    • A: We recommend running the stage 2 map with the following modifications: Turboback Exhaust with a high flow cat and a Cobb Sf intake system or a stock airbox with a stock air filter.

      Tyler.G 5 months ago

  • AnswerQ: Apexi N1 fitment  RobDizzle 6 months ago

    Will this fit with the Apexi N1 catback? And what else would I need? 02 wrx stock turbo.

    • A: Yes, this will bolt right up and you will want to purchase a new donut gasket for the bottom of the downpipe.

      Brady R. 6 months ago

  • AnswerQ: Bolts with pipe?  TheHamdog 7 months ago

    Does this include the bolts for install? or is it just the downpipe alone? I need to replace my spring loaded bolts.

    • A: This is just the downpipe alone. Your OEM hardware can be reused with the Cobb downpipe.

      brklynitalian12800 7 months ago

  • AnswerQ: Donut gasket  kmkja0234392 8 months ago

    will the oem donut gasket fit fine with this downpipe and a hks carbon ti catback ?

    • A: That is one of a few ways to fit this downpipe to a 3 catback, in some cases using the stock downpipe to 3 catback adapter will make fitment easier.

      Nick S. 8 months ago

  • AnswerQ: Wideband sensor fitment.  Lavjerj22942 9 months ago

    I have a question as to what thread pitch the extra bung is, or what brands you have found to fit said threads? Thanks, Jeremy

    • A: The bungs in any of our downpipes will fit any OEM sized oxygen sensors. This is not limited to but includes all wideband kits that we offer.

      9 months ago