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COBB 3" Catted (GESi) Downpipe: MAZDASPEED3 2007-2013
COBB Downpipe: Mazdaspeed 3
COBB Downpipe: Mazdaspeed 3

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Our Price: $875.00

Product Code: 571212


COBB Downpipe System
Application: Mazdaspeed 3

COBB 3” Downpipe for MazdaSpeed3 Features:
• Increased horsepower and torque
• CAD designed cast turbo outlet for maximum flow
• Minimal bends for less restriction
• 304 stainless steel throughout for corrosion resistance
• Custom spun metal substrate high flow cat
• Internally lined stainless steel flex section
• Three O2 bungs for factory sensors plus aftermarket
• Cross-welded and braced hanger section for added strength
• Polished tubing and cat for attractive finish
• Factory location of flex section eliminates stresses
• Stock donut gasket for optimal sealing and long life
• Compatible with all cat back exhaust that mate to factory downpipe

The COBB 3” Downpipe replaces a very restrictive element in the Mazdaspeed3 exhaust system. Considerable effort was spent designing a flow path with the fewest number of direction changes and minimal degrees of bend in order to eliminate restrictions. This beautifully fabricated downpipe delivers significantly improved exhaust flow, resulting in faster turbo response time and power gains across the entire rev range, while still protecting the environment with its highly efficient custom catalytic converter.

The engineering that went into the COBB 3” Downpipe started with the CAD designed investment-cast turbine outlet, made of 304 stainless steel for enduring corrosion resistance and reduced heat transfer to the engine bay. The shape of the outlet flange makes optimal use of the tight confines of the MS3's engine bay, smoothly blending turbine outlet and wastegate gases. The outlet flange is configured with two O2 sensor bungs; one to accommodate the stock O2 sensor and another with a pre-installed plug that can be removed to allow an aftermarket wideband O2 sensor or datalogging device with easy engine bay access.

A custom spun metal substrate high flow catalytic converter comes next. This one piece 400 grade stainless steel cat has a much higher flow rate and longer lifespan compared to ceramic or “brick” style cats. It also reaches operating temperature faster than other style cats for cleaner cold-start emissions. A third O2 sensor bung is located immediately after the cat to be used by the second OEM O2 sensor.

The stainless steel flex section used in the COBB 3“ Downpipe is internally lined (unlike most flex sections) and provides smoother exhaust flow and much longer lifespan for the steel braiding. The placement of this flex section in the factory location (before the first exhaust hangers) is critical in absorbing engine movement and eliminating damaging stresses that would otherwise be applied to the flange, cat, exhaust hangers and chassis. This increases the longevity of the downpipe as well as downstream exhaust components.

All tubing used in the fabrication of this downpipe is polished 304 stainless steel for increased corrosion resistance and a mirror-like finish. The 304 stainless steel hangers are cross-welded and well braced to eliminate a point of fatigue that is evident in other aftermarket downpipe designs.

The end flange uses the stock donut gasket and factory spring bolts to aid in flex, longevity and proper fitment. This provides an improved seal compared to other methods, as well as reduced noise. An additional benefit is that it makes the COBB 3” Downpipe compatible with any cat-back exhaust that mates to the factory cat section. When researching downpipes for your MazdaSpeed3, consider COBB's intensive engineering, quality of materials, impeccable fabrication and all around versatility. The COBB 3” Downpipe is unmatched in the marketplace!

Average Customer Review: Average Customer Review: 4.5 of 5 4.5 of 5 Total Reviews: 15 Write a review.

  0 of 3 people found the following review helpful:
4 of 5 Great Pipe/needs a tune March 28, 2012
Reviewer: Matthew Bleak from West Jordan, UT United States  
This is a great part but I now I really need to return my car.

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  2 of 2 people found the following review helpful:
5 of 5 Great Product with no problems March 21, 2012
Reviewer: MPSDAN from Brisbane, QLD Australia  
I have always heard that an aftermarket downpipe would improve the mazdaspeed's performance but it was always difficult to buy the right brand. Cobb has been renowned for their R+D and reliable products so i decided I'd go with their Downpipe.

This product has since made it hard for me not to smile everytime i enter my mazdaspeed. It sounds amazing and drives amazing. No smoking issues or droning. I hear most other brands experience CEL problems with aftermarket downpipes but not with the Cobb!

I had mated this downpipe with Cobbs Catback Exhaust and together makes one hell of a combination.

Thumbs up to Cobb for their excellent workanship and product!

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  0 of 0 people found the following review helpful:
5 of 5 WOW!! January 14, 2012
Reviewer: Joey from Bloomfield, NJ  
First of all do not attempt to do this outside if you live in shitty jersey lol.so started of smooth until one of the spring bolts on my hks exhaust totally seized it was about 8 pm and then it started to down pour so we had to stop.next day was blistering cold so we took out the compressor and decided to just cut the bolt.after that stock downpipe came out like butter.install of the cobb only took about 45 minutes.start up was not much different in sound but after i let it warm up for about an hour and some of the crap burnt up the difference was clearly noticable.But when u get on this thing the only thing you can do is smile. the sound is absolutely amazing mated to the hks.. i was a little skeptical about how much power u actually gain but the gains are more... so much more than just noticable.i am very impressed with this downpipe and would not go with any other one.the price is moroe than other downpipes but i promise its well more than worth it.

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  1 of 1 people found the following review helpful:
5 of 5 downpipe December 30, 2011
Reviewer: mike from san diego, ca.United States  
There is an increase in power.sounds the same compared to racepipe ...o2 sensors did not come off. Appears to be good quality..good pulls in 2nd and third..car  is a beast!!!!do highly recommend...

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  2 of 2 people found the following review helpful:
4 of 5 COBB DP September 1, 2010
Reviewer: Joshua Parsons from Orlando , FL United States  
This downpipe sounds great mated to my Mazadaspeed CBE. However it caused substantial smoking at idle within a few hours of install.  The only way to stop it was to also install an oil catch can. COBB knows this because I found a PDF from them online addressing this issue.   Everything has been great since the install of the OCC.

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