PART NUMBER: 61-1155
We are proud to offer our PLUG AND PLAY RoadsterSport Street catted header, all sensors stay in factory locations! This is the most torque you can buy in a catted MX5 Miata header. All Stainless Steel 1.6 inch primaries and proudly made here in the USA. See our forum MX5 PRHT Project and Dyno thread for many more details on development history, pictures of prototypes, and dyno work. A great choice for street customers looking for a Plug And Play MX5 Miata header! Sorry, we cannot ship these to residents of California.
MX5 Miata Street Header features:
-Longer, equal length runners
-High-flow 5" round, 200cpi Ceramic Core Catalytic Converter
NOT CARB APPROVED for California, the Carsound 99659HM core is an EPA certified converter covering up-to 6.2L/6375 lbs so it easily handles the flow of our performance header. But not CARB approved so it is not legal for street and/or highway driving in California. 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.
-Bolt-in design for USA and Canada LEFT HAND DRIVE MANUAL TRANSMISSION NC (see our forum header install thread for details of installation on automatic transmission).
-Bolts to RoadsterSport MX5 Midpipe...or stock MX5 midpipe. Also saves weight, factory header assembly is 15.2 pounds and this RoadsterSport MX5 Street Header with converter is just 11 pounds! Converter has two year manufacturing defect warranty (normally aspirated cars only, NOT recommended for supercharged cars or heavy autocross/track use), the rest is all stainless steel and has a LIFETIME warranty, even the flanges!
Currently for Manual Transmission only (a professional can install on the automatic but it requires re-engineering the cooling line layout and modification to the bell housing). Also, sorry to our Australian customers but this fits Left Hand Drive only.
We have included a number of extra features into our MX5 Miata Street Header which we believe customers will appreciate. We CNC machine the main flange to match the factory unit, including the bolt hole flange area thicknesses so that we are precisely replicating the factory fit to the head in terms of thread depth and space, etc.
Our collector outlet is 2.5 inches. Curiously, the factory outlet is ALSO 2.5 inches and then the factory exhaust chokes down after that point. For best HIGH RPM performance customers should match our header with our midpipe and exhaust so they are running 2.5 inches of flow all the way...but our header will bolt in place of the factory header and connect perfectly to the factory midpipe for better performance from idle to redline.
PICTURE OF FACTORY MX5 HEADER BELOW, Note the pinch point where the factory header suffers the primaries pinched in half, circled in red below. That pinch point chokes the power this Miata 2.0 motor can otherwise make. Our Roadstersport Street MX5 Header eliminates that pinch point, extends the primary length to max torque gains, while retaining a high efficiency converter.
BRIAN'S APPLICATION NOTES: We pushed the converter as far down against the lower flange as possible to maximize the length of our primaries to maximize the torque gains. Dyno Below shows results of configuration we expect most will run (RoadsterSport Street Header with Roadstersport Q midpipe and Roadstersport Q muffler). Low line best results with stock intake and stock exhaust, high line is results with this Roadstersport Street Header, Roadstersport Midpipe and Roadstersport Q exhaust (still stock intake). We expect many will leave factory midpipe in place and use this header with our RoadsterSport Q Muffler on the end (factory midpipe just a little smaller in diameter and we expect that keeping the factory midpipe would give similar results through the low and mid range and give up just a bit toward the high RPM range).
Notice O2 Bung BEFORE and AFTER Converter so you can keep your factory O2 Sensors inline and prevent engine codes. You can use the extension cords linked below, or you can release some O2 wire length from factory harness bracket to make the install without the extension cords (just follow the O2 cords back until you reach that bracket and this will become obvious).
Notice in dyno that the gains in torque are strongest at the low rpm range but extend through the mid range and all the way to redline, that's a torque improvement you can feel every time you pull away from a stop and every time you grab a higher gear! These are dyno results without doing a tune, adding our MotoEast Tune would add even more to your results.
HEAR the RoadsterSport Street Header for yourself on our 2012 PRHT Project Car along with our RoadsterSport Midpipe and RoadsterSport Q Muffler.
MIATA MX5-NC 2006-2015
* FREE SHIPPING
MIATA MX5-NC 2006-2015
* FREE SHIPPING
MIATA MX5-NC 2006-2015
* FREE SHIPPING
MIATA MX5-NC 2006-2015
* FREE SHIPPING
This is a package review. I installed a RoadsterSport MX5 Street Header, the RoadsterSport Helmholtz midpipe and converter and the RoadsterSport Super Q adjustable tailpipe. I also added the header blanket to the mix. I love the sound and the extra oomph. The exhaust tone is definitely more throaty and the power is increased with much greater urgency now. The sound is increased but not obnoxious at all, and cruising is about like stock. It has been an excellent upgrade, adding even more fun to the already enjoyable MX5. Thank you Good-Win Racing for all of the advice and direction in addition to offering great products.
The first section of my exhaust to be replaced was the mid-pipe. I went with the stainless. Then the muffler, and for that I went with the Roadstersport II. Not the super-Q - just the II.
So, this header was the final part of my exhaust system. Back when I bought the Roadstersport II muffler, I also ordered the optional baffles, but never installed them. But I knew I planned for a header eventually, so opted to keep the baffles in the event I did want them after the header was installed.
I've installed the header and still don't need the baffles. It's not much louder than it was with the stock manifold, stainless midpipe, and Roadstersport II muffler. It is maybe a little louder, but I think mostly a deeper tone rather than more real volume. It's more same volume but lower note. And I'm good with that. So for me, still no baffles needed.
Having the exhaust setup I had prior to the header, I had more deceleration burble before adding the header. So yes, to my surprise, adding this header to my prior setup did cost me some of (most of?) the burble I had come to like.
And yes - you can "feel the difference" in torque, but the fact is I don't normally drive the car hard enough to appreciate the difference. But I'm glad to have it when I do want it. It's not a huge difference, but noticeable if you're paying attention. It's that kind of change.
And as usual with Good-Win stuff - amazingly built. Quick ship, fast delivery.
I also Love my new header! Plus one for another painless AT install. My mechanic loved everything about the header and easy install. The detailed documentation was fantastic. The sound is exactly as shown in the GWR video and want I expected. I highly recommend this product. This is everything that should have been a factory option. Once upon a time Mazda offered a Mazdaspeed dealer exhaust option. The sound is deeper but not obnoxious. It turns a lot of heads coming form such a small car. If you need to tone it down you always have the Roadster Sport baffles. My last step is to schedule an appropriate tune to take full advantage of the Roadster Sport complete exhaust. Great job Good-Win!
Feedback is to either include your acceptable user written install documentation or at least provide Internet links provided by other Miata owners. Also provide a note in the sales advertisement that some of the heat shielding will NOT be re-used.
~ Dan S. Central Florida (MX-5, 2013 Club, AT)
This header is well made, easy to install, just a little problem with last bolt, but use a knuckled socket and extension works, also if you can get car on a lift, much easier, but can be done with car supports. There is a noticeable difference in engine torque, does not strain as much go up the reps, makes a nice sound too, also it is plug and play, the ECU will adapt to the header! I'd recommend, getting the the COBALT Forced Cold Air Tube - 2006-2015, 904-377 and a K&N replacement filter for the OEM filter box. It becomes a closed system, that projects cold air into the engine and stops water getting in the system too. Very inexpensive way to get cooler air to the motor.
There is a noticeable difference in the mid-range torque. It feels more eager to get going, keep in mind this is without a tune. I'm sure with a tune it would have even more gains.
I primarily picked up this header because the catalytic converters was on its way out and putting out a putrid sulfur smell due to high sulfur gasoline in my area.
If you struggle getting the header out and don't want to remove the alternator. Pull the o2 sensors and the studs off the bottom of the header. It is possible, but a tight fit.
Upgrading my exhaust one piece at a time. This was a good place to start. Very noticeable increase in torque. With only the header it isnt much louder at all but it does make the sound deeper and adds a little burble on the over run. I would recommend.
Love my new header! Had my mechanic do the install and he said it went well. The sound is deeper but not loud at all. Love the burble! Combined with a tune, it's pulling harder too! Thanks Good-Win!
Significant increase in power and performance. The Engine breathes much better now with this Header very glad to have it on my ride now.
After reading many other positive reviews on both the GWR and Miata forums I finally decided to buy this product. My main concern for many months was whether or not I was up to the task of installing the header. But with the excellent instructions on Brian's forum as well as several Miata forum threads it turned out easier than I expected.
After receiving notice that the header would arrive on a Friday afternoon, I began the disassembly process. After about 3 hours I had the stock manifold out. Later that afternoon the new catted header arrived right on schedule. And it is a thing of beauty. I opted for the stainless version. Installation on Saturday morning took another 3 hours, although I could have shaved some time off of that but I was actually enjoying the process of double checking torque values and cleaning up my engine compartment. I already have the GWR catted midpipe, so that connection was a snap.
I put everything back together, reconnected my battery, and went for a drive. NO CODES! Nice throaty sound with my RSII muffler, and a significant boost in power and low/mid torque. Another happy camper here. I since have added a M-E tune and I feel I have realized all of the gains that Brian has achieved on his 2012 project Miata. I've put several hundred miles on my Miata since the install with zero problems. This is the car that Mazda should have built all along. Thanks Brian.
I just wanted you guys to know how much I love this header. I bought it back in December and had it installed just after Christmas. Well this being Washington State it has rained since then. I finally got to get out and drive it for a few days. She barks now coming out of first gear without taking the DSC off. I bought the Glass pack baffles thinking it would be too loud but running the "Q" exhaust I have had no need to install them. This is one upgrade that gets the thumbs up! If you bought the car and thinks it is missing something BUY this header. You will not be disappointed.