PRE-ORDER ONLY - Catted Expected to ship in ~ July.

Mazdaspeed 3, 3.5 inch performance exhaust downpipe for the 2007-2009 and 2010-2013 Speed3 model years

Let your big turbo build breathe easy with the CorkSport 3.5” Downpipe for Mazdaspeed 3! A cast stainless bellmouth feeds huge 3.5” diameter piping so your speed is free of restriction, at just about any power level. With the size also comes decreased spool times and we even optimized the design so it is just about the easiest downpipe to install on your MS3. Check out more information and pictures down below!

This is the Downpipe Only Kit, designed to connect to performance 3inch or 80mm Cat-Back Exhausts that use the OEM style donut gasket. This will not connect to the CorkSport 3.5” Turbo-Back Exhaust. If you want a FULL 3.5” exhaust then check out the CorkSport 3.5” Turbo Back Exhaust HERE for GEN1 and HERE for GEN2!

#Mazdaspeed3!

The CorkSport Advantage

Performance Focused:

The CorkSport 3.5 inch Downpipe is designed to get the best out of your Mazdaspeed. The large cast bellmouth design and huge 3.5” OD piping offers plenty of flow to efficiently support ~850+ WHP. While this power potential may be beyond your goals; in lower power builds (like a built engine and CST5 Turbo) we have seen spool & transient response improvements.

200-400 RPM faster spool could be expected depending on the exhaust setup you are moving from. We’ve seen this on CST5 turbo-built setups with manifolds. Smaller frame turbos such as OEM K04, CST4 turbo, and BNRs3/4 will see similar results. While larger frame turbos like the CST6 turbo will see great results but are more dependent of the manifold and cylinder head setups.

Fitment Inspired:

We know that one of the biggest challenges when upgrading your MS3’s downpipe is the installation itself. We aimed to remedy at least some of the headaches with the CS 3.5” downpipe. By separating the upper and lower sections of the downpipe, all downpipe nuts are now easier to access as you do not have the lower section in the way while tightening. We allowed for easy stud & nut access as well with cutouts designed to fit sockets & wrenches. Finally, should you ever need to remove the downpipe or turbo for maintenance; the bellmouth portion can stay attached at the turbo! Just disconnect the v-band clamp and remove the lower DP section from the exhaust.

Mazdaspeed 3 catted downpipe for your exhaust

Fitment for 3 inch/80mm Exhaust:

The CorkSport 3.5” Downpipe Only Kit is designed to fit an upgraded 3” or 80mm exhaust that uses the OEM style donut gasket for an easy install with your existing pipes.

Catted & Catless:

The CorkSport 3.5” Downpipe is designed to fit an upgraded 3” or 80mm exhaust that uses the OEM style donut gasket for an easy install with your existing pipes. Offered in both catted and non-catted setups. Both are for race use only and are not street legal in areas with emission controls. The catted setup uses a high flow 3-way metallic foil 300cel CAT with a 4 inch outer diameter.

Materials & Manufacturing:

Starting at the turbocharger, the CS 3.5 inch downpipe uses a cast 304 stainless steel bellmouth for strength and reliability. The piping uses CNC machined V-band flanges TIG welded to mandrel bent 304 stainless piping. CNC machining ensures a leak-free seal, TIG welds ensure high strength, and mandrel bend ensure smooth exhaust flow. All combine to make a downpipe that looks, sounds, and performs great that will take just about whatever you can throw at it

Hardware and Accessories:

Included with your 3.5” downpipe is everything needed for installation. This includes the stainless v-band clamp for the bellmouth to DP connection, brand new downpipe mounting studs & lock nuts, a new donut gasket at the midpipe, and even an O2 sensor harness extension for catted customers. We’re most proud of our custom MLS downpipe gasket included with each kit. We port-matched it to the DP bellmouth & CST6 to ensure no flow restrictions whatsoever!

For off-road & race use only. This means keep it on the track and not on the highway.
A check engine light (CEL) will be illuminated on catless and some catted setups as a result of installation.
This is the Downpipe Only Kit, designed to connect to performance 3inch or 80mm Cat-Back Exhausts that use the OEM style donut gasket. This will not connect to the CorkSport 3.5” Turbo-Back Exhaust.
CATLESS ONLY: Strongly advise against combining the catless downpipe with a KO4 or CST4 IWG. Overboost/boost spiking may occur on some IWG and EWG setups. Refer to the fitment tab for details.
3inch or 80mm cat-back exhaust required for installation. Does NOT fit with OEM cat-back exhaust.
Does not fit with CorkSport 3.5” Exhaust. You must purchase a full turbo-back exhaust to get full 3.5” pipes.
If you have a CorkSport Turbo with external wastegate housing, the wastegate will need to be moved to the turbine housing directly and a new dump tube used. Check out the CS EWG Dump Tube for 3.5” Downpipe for more information.
Only fits on turbochargers with OEM downpipe flange shape.
If you have a CS exhaust manifold with EWG on the manifold, the EWG dump tube will fit with CS 3.5” downpipe.

Additional Features

Vehicle Fitment:2007-2009 1st Gen Mazdaspeed 3 and 2010-2013 2nd Gen Mazdaspeed 3.
Designed & Developed in America: Designed, tested, and validated in Vancouver, Washington, in the Pacific Northwest.
CorkSport Service & Support: Receive a 2-year warranty, full-color installation instructions, all of the needed installation hardware, and knowledgeable telephone installation support at(360) 260-2675.

How To Install The 2007-2013 Mazdaspeed3 Downpipe

It will take you 5 hours to install the Speed 3, 3.5-inch Downpipe with our installation instructions.

5 Hour Install Time

4/5 Difficulty

2-Year Warranty

Yes CEL

CS's new downpipe designs with the V-band bell mouths are the only options I would consider for this platform at this point. This design saves so many headaches that it's hard to quantify all of it unless you were doing 2 installs beside each other to compare...

If you are doing DP, Mani and Turbo all at once like I was, these designs are straight cheat codes and will likely save you HOURS not minutes.

The 3.5 version is LOUDER (even catted) there's no getting around it...
This thing made my semi quiet Cobb exhaust become loud as FUUUUU (this was effected by the CS manifold as well of course) so be prepared for that.
It sounds awesome of course just a touch louder than I planned when all was done.

Highly recommend CS's downpipe and exhaust mani designs with the vbands... Anything else is just punishing yourself unnecessarily.

Nathaniel Kemp01/20/2025, 03:05 PM

I've got the catted version of this downpipe because my previous setup (different brand) has failed. One of my concerns was if the 300CPS cat would still make 500+bhp, and it does. Thankfully my new setup with the CS catted DP (+ one more added 400CPS cat) is quieter than the previous setup (de-catted DP after the cat failed, catted + resonated TP).

Emissions are also just fine. I removed the spacer for the secondary O2, and there is no CEL. This is on a 3MPS BK/speed3 gen1; the gen2/BL may be a bit more sensitive to this and may still benefit from the spacer.

While the old DP was a nightmare to remove/install with the engine in the car, this one was a breeze! Also a ton easier to get out and back in if I will need to change anything (flex pipe, cats, and so on).

Victor Tarhon-Onu02/25/2024, 11:59 AM

QUALITY
Beautifully made - a real shame it’s tucked under your car and out of view. The welding is amazing; you’ll find yourself just sat admiring it prior to install.

INSTALL
Excellent - the decision to split the bell mouth from downpipe is inspired and makes the process straightforward. This was the main reason I went with this over the standard 3” downpipe. I installed this by myself over several hours (along with a cat back exhaust and TMIC). Removal of the original exhaust system was about 75% of the total time.

PERFORMANCE
Holy cow - with the help of Purple Drank and in conjunction with the 3" cat back, the downpipe worked its magic on my car. It’s spooling earlier and harder. I’m still running OEM turbo with the catted downpipe and only occasionally spring a CEL.

SOUND
Like thunder! Not too loud until you’re getting on it; cold starts will make the hairs on the back of your neck stand up for sure.

CONCLUSION
I’ve been wanting to upgrade the exhaust for several years but had been put off by how difficult the install would be. The split system of the 3.5” downpipe mitigates most of the problems and while it’s not an easy install, it’s not really that bad if you take your time. Is it too big for standard turbo? maybe; however I wanted to future proof my investment, knowing that I will at some point replace the OEM turbo for a larger unit. Excellent system!

Russ Forsyth01/13/2023, 08:59 AM

Write a review

Corksport manifold with the external watergate and stock turbo with factory waste gate welded shut corksport 3 inch cat back would i still experience or have issues with boost spikes etc if i installed this 3.5 inch downpipe ?

Asked by Hamish | 02/01/2025, 10:49 PM | 1 answer(s)

will this downpipe fit the 3" corksport cat back

Asked by mitchell katona | 06/08/2022, 06:14 PM | 1 answer(s)

Why is there an unwanted CEL on some catted setups?

Asked by Carlos Sierra | 04/20/2022, 08:51 PM | 1 answer(s)

Will the o2 sensor clear the external waste gate on a cpe manifold with this downpipe?

Asked by Jason Wumbo | 03/04/2022, 08:56 PM | 1 answer(s)

Before asking fitment questions with turbos please take a look at the Fitment tab of this product listing for specific notes for turbos and exhausts.

Asked by CorkSport | 11/18/2021, 06:23 AM | 0 answer(s)

New post

Mazda performance parts financing is available with CorkSport

Looking to finance your parts purchase and want to get 6 months NO interest on any purchase over $199? Click on the image above for more details.

Fits:
2007-2013 Mazdaspeed 3 Hatch
2007-2013 Mazda 3 MPS

Tuning: With the larger 3.5" piping we have found that some IWG (and possibly some EWG setups) will not be able to control boost as well due to the improved flow.

OEM K04 = CATLESS ONLY: Possible Mild Boost Spike Not Recommended

CST4 IWG = CATLESS ONLY: Possible Boost Creep to ~24psi (auxiliary fueling PI or methanol required) Not Recommended

OEM K04 = CATTED ONLY: Good (no spike or creep) (CS Manifold and EWG Turbine Housing Tested)

CST4 IWG = CATTED ONLY: Good (no spike or creep) (CS Manifold and EWG Turbine Housing Tested)

CST4 EWG = Good (no spike or creep) (CS Manifold and EWG Turbine Housing Tested)

CST5 IWG/EWG = Good (no spike or creep) (CS Manifold and EWG Turbine Housing Tested)

CST6 EWG = Good (no spike or creep) (CS Manifold and EWG Turbine Housing Tested)

ATP Turbo = Not Tested

BNR Turbo = Not Tested

Russ Forsyth

01/13/2023, 08:59 AM

Comment
QUALITY
Beautifully made - a real shame it’s tucked under your car and out of view. The welding is amazing; you’ll find yourself just sat admiring it prior to install.

INSTALL
Excellent - the decision to split the bell mouth from downpipe is inspired and makes the process straightforward. This was the main reason I went with this over the standard 3” downpipe. I installed this by myself over several hours (along with a cat back exhaust and TMIC). Removal of the original exhaust system was about 75% of the total time.

PERFORMANCE
Holy cow - with the help of Purple Drank and in conjunction with the 3" cat back, the downpipe worked its magic on my car. It’s spooling earlier and harder. I’m still running OEM turbo with the catted downpipe and only occasionally spring a CEL.

SOUND
Like thunder! Not too loud until you’re getting on it; cold starts will make the hairs on the back of your neck stand up for sure.

CONCLUSION
I’ve been wanting to upgrade the exhaust for several years but had been put off by how difficult the install would be. The split system of the 3.5” downpipe mitigates most of the problems and while it’s not an easy install, it’s not really that bad if you take your time. Is it too big for standard turbo? maybe; however I wanted to future proof my investment, knowing that I will at some point replace the OEM turbo for a larger unit. Excellent system!

Victor Tarhon-Onu

02/25/2024, 11:59 AM

Comment
I've got the catted version of this downpipe because my previous setup (different brand) has failed. One of my concerns was if the 300CPS cat would still make 500+bhp, and it does. Thankfully my new setup with the CS catted DP (+ one more added 400CPS cat) is quieter than the previous setup (de-catted DP after the cat failed, catted + resonated TP).

Emissions are also just fine. I removed the spacer for the secondary O2, and there is no CEL. This is on a 3MPS BK/speed3 gen1; the gen2/BL may be a bit more sensitive to this and may still benefit from the spacer.

While the old DP was a nightmare to remove/install with the engine in the car, this one was a breeze! Also a ton easier to get out and back in if I will need to change anything (flex pipe, cats, and so on).

Nathaniel Kemp

01/20/2025, 03:05 PM

Comment
CS's new downpipe designs with the V-band bell mouths are the only options I would consider for this platform at this point. This design saves so many headaches that it's hard to quantify all of it unless you were doing 2 installs beside each other to compare...

If you are doing DP, Mani and Turbo all at once like I was, these designs are straight cheat codes and will likely save you HOURS not minutes.

The 3.5 version is LOUDER (even catted) there's no getting around it...
This thing made my semi quiet Cobb exhaust become loud as FUUUUU (this was effected by the CS manifold as well of course) so be prepared for that.
It sounds awesome of course just a touch louder than I planned when all was done.

Highly recommend CS's downpipe and exhaust mani designs with the vbands... Anything else is just punishing yourself unnecessarily.