RoadsterSport Stainless MX5 Midpipe with Converter NC GR-008

  • Sale
  • Regular price $749.00
  • incl. GST


Designed as a bolt-on replacement for the factory MX5 midpipe to carry the 2.5 inch outlet of the factory header, and our RoadsterSport and Racing Beat headers, all the way to your choice of any of our 2.5 inch inlet RoadsterSport mufflers. Simple Bolt on for MANUAL TRANSMISSION ONLY, can be installed on Automatic but see page four of our forum header install thread for details of what is required. Also bolts up to our Racing Beat exhaust, MazdaSpeed exhaust, stock header and Racing Beat header.

INCLUDES TWO O2 SENSOR CONNECTIONS which gives YOU the option to later add our RoadsterSport or Racing Beat headers and avoid engine codes (by using our O2 plug and play extension cords to relocate the factory O2 sensors to before and after the converter in this midpipe).

All stainless steel construction for years of driving pleasure. This MX5 midpipe is slightly larger diameter than stock at 2.5 inches all the way through (see torque gains in our forum dyno thread). Uses high quality SPUN catalytic converter with metal core. Uses monster 18 inch resonator because when you uncork this NC MX5 motor it wants to get loud unless you use a resonator this large (by comparison stock resonator is about a foot long).

Stock midpipe is 9kg, our midpipe is 7.5kg  for total savings of 1.5kg. Despite very large resonator, this midpipe will raise the final sound level just slightly because of the higher flow larger diameter tubing.

FREIGHT & SHIPPING NOTE: Due to the size of the mid-pipe box delivery can only be made to non residential addresses. Please email info@mx5parts.com.au after placing your order and we'll work with you to find the best delivery solution.


Brian GoodwinBRIAN'S APPLICATION NOTES: We started with the much larger "two biscuit" cat we use in the 99-05 midpipe system but I didn't like the sound quality that resulted. This small single biscuit spun unit is actually more expensive than the big metal clamshell cat we use in the 99-05 system but we did some experimenting with cats of different sizes and the short chambered spun cat helps reduce that 3000 rpm DRONE/ BOOM that this motor really wants to make on decel when uncorked. The short cat also saves another 1.5kg as compared with the bigger cat.

As for sound level...with the big cat the sound volume level was really unchanged as compared with the stock midpipe but we made the tradeoff decision to reduce decel drone but finish with slightly higher overall volume using the short chambered spun cat. and I think most will appreciate this choice.

INSTRUCTIONS....see installation instructions in our forum in the Instructions Section HERE.

INSTALL NOTES and CAUTION! Is one or more of your ignition coils weak or failing? One reason people buy this midpipe is that their factory midpipe converter has failed after 80,000 or more km's. The owners too often assume the failure is simple old age. Failing items such as coils, fuel pressure regulators, spark plugs, valves, plug and ignition wires, and improper ECU calibrations, can cause the engine to misfire and dump raw fuel into the catalytic converter, which will cause over heating and a meltdown in the converter, which is not a manufacturing defect in the converter. If you simply replace the midpipe and don't fix the failing car then you can expect to quickly kill any replacement converter and that replacement will NOT be a warranty replacement. Therefore, please have your car professionally inspected and repaired BEFORE you install your new midpipe.

INSTALL TIP: READ our installation notes in our forum Installation section, the slip joint in the middle is your friend and the mistake some will make is to shove both sides of the midpipe fully together, making it too short. Lube up that slip joint and adjust length as needed.