Good-Win Racing Mazda Performance Parts

RoadsterSport MX5 Miata Midpipe with Converter


Miata MX5 2016-2018 · Exhaust

Part Number: 61-1734

Application: 2016-2018

Reg. Price: $599.00

Sale Price: $499.00


RoadsterSport MX5 Miata Midpipe with Converter
rating (0 Ratings)
rating (0 Ratings)

Thank you. You have rated this product.

Sorry, this product is not available to residents of California.
Add more torque and a little more sound with our all stainless top of the line RoadsterSport All Stainless Midpipe!

Mazda gave us a serious challenge with the ND midpipe design but we got it figured out. Instead of the small ball/socket outlet of the stock midpipe we convert to a flat flange so we can carry more flow all the way out through any of our RoadsterSport mufflers. That means this midpipe ONLY works with our RoadsterSport brand mufflers. To replace the function of the ball/socket connection but allow for greater flow we use a stainless flex joint. The stainless flex joint adds significant costs but was the best way to max flow and performance all the way out. Likewise we stuff the largest and highest density packing all stainless resonator that can fit on the car so that even with greater diameter and flow the sound is mellow and fun, not harsh and abrasive.

All Mandrel bent tube with no tight bends to slow flow, see the picture and notice how smooth and flowing the bends are!

Designed as a bolt-on replacement for the factory midpipe to carry higher flow from larger pipe size all the way out any of our RoadsterSport mufflers. Simple Bolt on! Does NOT fit with factory muffler.

INCLUDES TWO O2 SENSOR CONNECTIONS which gives YOU the options later when adding headers (relocating the factory O2 sensors to before and after the converter in this midpipe from their stock location before and after the converter that is in the factory header when you replace that header to help avoid codes.).

All stainless steel construction for years of driving pleasure. This MX5 Miata midpipe is larger 2.5 inch diameter pipe size (see torque gains in our forum dyno thread). Uses high quality SPUN catalytic converter with metal core (despite presence of converter this unit is not CARB approved...which makes it legal in California only for off-road/race track use). Uses monster size because when you uncork this ND Generation MX5 Miata motor it wants to get loud unless you use a resonator this large (by comparison stock resonator is much smaller).

Despite very large resonator, this midpipe will raise the final sound level slightly because of the much higher flow design.


INSTRUCTIONS....see installation instructions in our forum in the Instructions Section, RoadsterSport Midpipe install page 4 and beyond. The smart customers will print those instructors for their mechanic so the mechanic is not trying to figure things out in the dark! Note this unit is plug and play on Manual Transmission cars but Automatic cars have a small tab that must be cut off for fitment of this bigger diameter unit, see forum pics. Brian's tips for easy install. You can push the joint between two halves any direction you need before applying torque to hold it's length and position. For sensor connection you likely will find it easier to unplug the sensor from where it hangs and from it's electrical connection near that point, install in midpipe and only then reconnect the plug, etc.

NOTE one gasket is included, for the midpipe exit to join with the muffler. For the front connection to stock header you stick with the factory ring gasket already on stock header outlet. If changing to our Max power header, that header will come with a gasket for that junction.

STR LEGAL under Class Rules Update 2012. Pursuant to SCCA 14.10.E: our cat fits entirely in the space that the factory cat occupied pursuant to SCCA 14.10.E....and maker certifies the core for use in any application up to 6.2L and 6000 pounds. Core has 25,000 mile manufacturing defect warranty (no core warranty for boosted or track cars), and the rest (including housings) are stainless and include a lifetime warranty.

BRIAN'S APPLICATION NOTES: I love the sound of this midpipe in combination with our RoadsterSport Helmholtz mufflers, adds burble and throatiness when you push toward redline and controls the off throttle resonance these motors will otherwise make. We could have done a cheaper midpipe, but we decided to do the best for those of you who demand the best.

INSTALL NOTES: At the connection from midpipe to muffler the factory setup uses springs but you remove the springs in the use of our midpipe which converts to standard flat flange setup. That means you are using the factory studs and nuts again at the connection to muffler with the spring function being handled by the flex joint a few inches up the system.
*** Product images may differ from actual product appearance ***


You guys are great! The new suspension is in and the ride is much improved. Thanks for the great service.

-- Chuck

I absolutely love my Roadster Sport headers, mid pipe and Q muffler. I have owned a lot of cars over the years and the quality of your product is truly exceptional. The ability to tune the Super Q is very much appreciated.

-- Tony G.