RoadsterSport HighFlow Stainless MX5 Miata Midpipe with HighFlow Converter

DESCRIPTION

Designed as a bolt-on replacement for the factory 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. Also bolts up to our Racing Beat exhaust, MazdaSpeed exhaust, stock header and Racing Beat header. For those with automatic transmission, look to our Helmholtz Midpipe which is available with 4" converter to fit the automatic and which has better drone control which is needed with the auto trans that sticks you in low cruising rpms where that drone is found.

Now using our ultra flow FIVE inch converter. Old 4 inch converter flowed just enough for 2.0 motors normally aspirated, but those same 2.0 motors get no downside with going with the 5 inch converter, and the 5 inch converter can handle more heat so a better fit for high performance uses. The big 5 inch converter is also perfect for boosted cars and 2.5 conversions. Five inch converter fits manual trans only.

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 Miata 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 (despite presence of converter this unit is not CARB approved...which makes it legal in California only for off-road/race track use). Note that there are states in addition to California that now follow the California model and require CARB compliance, please check the rules of your state before ordering, in some states this setup is legal only for race cars and may never be used on public highway.

Uses monster 18 inch resonator because when you uncork this NC MX5 Miata 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 20 pounds, our midpipe is 16.5 pounds for total savings of 3.5 pounds. Despite very large resonator, this midpipe will raise the final sound level just slightly because of the higher flow larger diameter tubing.

BRIAN'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 1.5 pounds 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.

SORRY, NOT CARB APPROVED FOR CALIFORNIA RESIDENTS. Sorry, we cannot ship these to residents of California.

Read full installation hints and notes in our forum Installation Instruction Section! --- CLICK HERE TO READ MORE.

STR LEGAL under Class Rules Update 2012. Pursuant to SCCA 14.10.E: our cat is smaller than stock but fits entirely in the space that the factory cat occupied pursuant to SCCA 14.10.E....and Magnaflow certifies these cores for use in any application up to 6.2L and 6000 pounds. Cat core has 2yr/25,000 mile manufacturing defect warranty (no core warranty for boosted or track cars), and the rest includes a lifetime warranty.

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 50,000 or more miles. 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.

Warranty note on the converter: warranty covers defective converter only. But you can burn up a cat with abnormally high exhaust gas temperatures from track use, supercharger, aftermarket ECU tune, ignition system failure causing a rich mixture, and more. Warranty does NOT cover damage to the cat from these external variables. A failed cat must be sent to the factory for inspection before it can be determined if it is covered under warranty or not.

NOTE we have ended the polishing of the setup because costs have jumped so much and we didn't want to further increase the retail price. Polishing added no function, so we did away with it to keep the price more affordable.