Skip to content




An extensive amount of engineering time was poured into developing the COBB MAZDASPEED3 SS 3″ Downpipe to produce the best all around option for the market.

Starting 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 bellmouth 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 also contains two O2 sensor bungs to accomdate the stock O2 sensor and offer the option for additional sensor installation to suit each individuals needs.

Next comes the custom spun metal substrate high flow catalytic converter. This single piece 400 grade stainless steel cat provides a much higher flow rate and longer lifespan than the typical ceramic or “brick” style cats common seen without sacrificing the ability to quickly reach proper temps for cleaner cold-start emissions. We also made sure to include one more bung just after the cat for the second OEM O2 sensor.

Right after that comes the stainless steel flex section which is internally lined to protect the steel braiding while maintaining optimal exhaust flow. The placement of the flex section just before the first exhaust hanger is important as well. This minimizes the effects of engine movement on the cat, flanges, and remaining exhaust components. Plus, the use of the factory donut flange design allows for compatibility with any cat-back exhaust designed to work with the factory cat section.

Lastly, all tubing and hangers are manufuctered using corrosion resistant 304 stainless steel with a beautiful mirror polish to make sure the downpipe looks as good as it flows and sounds.

Installation of any aftermarket Mazdaspeed3 downpipe requires an upgraded Cam Shaft Driven Fuel Pump (CDFP) and tuning to ensure adequate fuel supply and safe engine performance.


The COBB 3″ Downpipe is one of the key upgrades for the MAZDASPEED3 to unluck a huge amount of torque hidden away within the MZR 2.3 DISI Turbo engine from the factory. Considerable effort was spent designing a flow path with the fewest number of directional changes and minimal degrees of bend in order to eliminate restrictions that have been found in the stock system. This beautifully fabricated downpipe delivers significantly improved exhaust flow, resulting in faster turbo response time and power gains across the entire rev range.


  • CAD Designed Cast Turbo Outlet for Maximum Flow
  • 200 Cell High Flow Catalytic Converter
  • Three O2 Bungs for Factory & Aftermarket Sensors
  • Factory Location of Flex Section Eliminates Stresses
  • Utilizes Stock Donut Gasket for Optimal Sealing & Long Life


Weight 45.58 lbs
Dimensions 12 × 12 × 44 in


There are no reviews yet.

Only logged in customers who have purchased this product may leave a review.