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Mazdaspeed downpipe/catalytic converter upgrade

Mazdaspeed downpipe/catalytic converter upgrade
Mazdaspeed downpipe/catalytic converter upgrade
More power and faster spoolup for the Mazdaspeed.

Made in the USA

Exclusive to Flyin' Miata

Mazdaspeed downpipe/catalytic converter upgrade (Federal catalytic converter): 5 in stock
Mazdaspeed downpipe/catalytic converter upgrade (CARB legal cat): out of stock. Sign up to get notified when this product is back in stock.



Replace the restrictive and heavy downpipe on your Mazdaspeed with this 2.5" stainless steel version. When combined with our Mazdaspeed exhaust, it offers noticeably faster spoolup and a good increase in power. We measured a 23 hp and 26 lb-ft increase on our dyno. If Mazda had delivered the car like this from the factory there would be a lot less interest in aftermarket upgrades! An extremely popular upgrade for Mazdaspeeds.

Beautifully made out of stainless steel with polished flanges, this is a long-lived upgrade. So long that we offer it with a lifetime warranty. It`s also 7.2 lbs lighter than stock as an extra bonus.

5 year/50,000 mile warranty on the catalytic converter body, the internals (and ability to pass an emissions test) are covered for 25,000 miles, everything else is covered for life. Fits the Mazdaspeed with stock turbo only.

 Please note that we cannot ship this part to California as the catalytic converter does not have an EO number.

Additional Information

Additional Information

Part number 06-5830x
Fits: MSM
Manufacturer Thermal R&D
Flyin' Miata exclusive Yes
Fits Exocet? Yes
Proposition 65 Warning: Cancer and reproductive harm

Customer Reviews 7 item(s)

A Great Performance Addition!!!
This product is very nice and clean. The instructions on this website for installation support was very helpful. The only problem I faced was that the front triangle flange that connect to the back side of the turbo flange was not completely flat. It did not seal completely. It appeared as if the flange may have been warped during manufacturing during the welding process. It was an easy fix with some machining down. Otherwise a very nice fit!
Review by ALEX / (Posted on 4/3/2018)
Best yet!
This is probably the single best simple mod I have made to a car in 50+ years of driving.
Power flow is smooth, torque is more even throughout the range, combined with a cold air intake this will easily outperform the new ND Mx5.
Expensive to get it to Canada, but worth it!
(originally posted 5/5/2017)
Review by Crangetti / (Posted on 9/28/2017)
Great part, wish I bought it earlier
Had it two weeks now, wish I bought it earlier. Perfect fit, nice finish and instant results. I already had the full intake and this sets that off even better. Quicker spool up, smoother mid range and up top. Adds a nice rumble to the still stock exhaust. Easy to install once you get the old pipe out. Opted to install a wideband that had the o2 bung ready and at an angle to clear underneath the car perfect. I'd recommend this mod. I probably will get the exhaust next, but the sound now is even very nice.
(originally posted 8/23/2016)
Review by Chris / (Posted on 9/28/2017)
Love the service and advice Thanks again
Just installed the new downpipe and exhaust, it sounds Purrrrfect! just the right amount of deep sound without being too raspy. Love It!!
(originally posted 4/7/2016)
Review by John '94MSM / (Posted on 9/28/2017)
10/10 I do recommend!
Combined with the midpipe and exhaust for MSM, this thing is part of the equation that equals the perfect solution for us stock-turbo MSM owners. Good response when the spool begins to build up. Boost feels more linear, which says a lot for these MSMs. Highly Recommended upgrade, should be a staple in a list of upgrades for an MSM.
(originally posted 2/7/2016)
Review by Drkmiataknght / (Posted on 9/28/2017)
Outstanding quality, fit, and finish. Would definitely recommend.
(originally posted 9/23/2015)
Review by Jcald / (Posted on 9/28/2017)
Fitted up good, sounds good, runs good. put out the check engine light after battery disconnect and reconnect.
After installed, 5 stars. The installation was tough due to no lift. Jacked it up first one side then the other to get it high enough to work under with a creeper. Hard to get torque on nuts due to restricted space, but can be done. Maybe being 72 years old might have had something to do with that. A challenge but if I could do it anybody can!. $1960 to install new cat converter at dealer! I am a very happy Mazdaspeed Miata owner!
(originally posted 6/7/2015)
Review by Ken / (Posted on 9/28/2017)
Instructions for this part are not currently available online.

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