RoadsterSport HELMHOLTZ RACE MX5 Miata Muffler!

Exhaust has been on my car for a few weeks now, ran it with and without the baffle. I daily drive my car so it was important I didn't get something I would regret having. I love the tone it has with the baffle in and the top down. You get a nice low growl that I didn't notice with the baffle out.
Top up you can't really hear the growl you just get some louder lower exhaust note, a little drone on decel from 2000 down below 1500rpm. Baffle out, the low bassy drone on decel in low rpm gets a little louder. I still think baffle in, top down is the way to go for sure. The growly subdued tone you get with it just sounds too good. I don't think you gain much from removing it other than volume and a more bassy note to it. Goodwin has a video on YouTube of the race helmholtz where the camera is pointed at the tip and it's a really good representation of the growly note I heard with the baffle in. (Even though the video didn't show one installed) I like the note so much that I've been running top down as much as possible to hear it, even running heat and heated seats on full blast in low 30 degree weather. As a daily driver, even top up with radio on the exhaust isn't intrusive if you don't want it to be. Not loud enough to be obnoxious. Only thing that gets me is the empty cut out in bumper where another exhaust tip should be. Otherwise this is such a nice exhaust note to listen to

-- Sean G., Atlanta ga ( 2013 prht 6at ) December 2023

Thanks to Brian Goodwin for producing top quality NC upgrade products. I have his clutch, flywheel, all Progress suspension and B6 Bilstein shocks, upgraded brakes, catted header, carb legal midpipe and this Helmholtz race muffler. The sound quality and volume is perfect for this sports car. Thanks Goodwin Racing and Rocky for the suspension and clutch install.

-- John S., Ca. ( 2013 Club MX5 ) June 2023

Having read numerous reviews about sound and personal preference, I can totally understand that it's challenging to discuss/recommend sound levels and who may appreciate or dislike a particular note. For me, I've had my NC for a bit less than a year and love it. I previously owned an NA when I lived in Hong Kong and only had some suspension work done there. Back in the US, with garage space and tools, it's a new ballgame.

A big factor for me was the ability to live with a Hard Dog hitch (for various bikes I ride). This system looked to match and for sure, it does.

First - simple install. I did put my car on jackstands as it is somewhat low with an aftermarket suspension, Straightforward removal and install, plenty of room for my hitch. I'd guess that there's plenty of room for most hitches, but I can only speak to the Hard Dog hitch.

Sound, as Brian noted, is likely very personal. I bought the optional baffle and have swapped between the two and love the sound of both. To me, there's not a big difference, and I love the sound of both. To note, I used to run my (older) VW Rabbit GTI with a cherry bomb (straight through post-cat exhaust) and enjoyed that sound, I currently have the baffle installed because I like the look and there's not a big sound difference to me, I could likely have been happy with something louder, but I'm perfectly happy with this,

So - nice job on this exhaust. For those looking for hitch clearance, I can attest to more than sufficient clearance for a Hard Dog hitch. Others, I don't know, but I'd suspect there's plenty of room.

-- John G., Portland, CT ( 2013 PHRT Club ) September 2022

Had the RoadsterSport II Duals on the car from the previous owner. Great sounding muffler, but for my taste its more-bass-and-less-rasp than I prefer.

I am two weeks into daily driving this new single. It exceeds my expectations, giving the exhaust note the angry race-car-theater I want on the loud pedal, but without the low rpm resonating bass. The helmholtz kills those deep tones below 2100 rpm, and leaves the 3-5k rpm range with a smooth raspy note that is perfect. Total exhaust volume may be similar to the RSII, but the bass cutoff and mid-range tone makes it feel like it's far less intrusive. Passengers confirm it's easier to live with around town. A bit of burble on the 1-2 and 2-3 upshifts. Bought the baffle, haven't even tried it, sounds too good as-is.

Very satisfied customer!

-- Chad L., Washington ( 2006 Sport ) October 2021

Previously had a full 3" exhaust on my Civic Si that I had to design my own helmholtz resonator for since the drone on the freeway (3k - 3.5k rpms) was unbearable, so when I saw that Goodwin sells an off the shelf muffler with a helmholtz attached to it, I knew it was legit stuff.

Have put about 50 miles with this muffler with the car (stock header/midpipe/intake) and can 100% say with confidence that there is no drone at any RPM under partial and full throttle. There is a tad bit of drone from 1.5k -2k rpms off-throttle during deceleration, but honestly its rare that I am in that rpm range. The muffler has a deep tone to it, yet there is no boomy-ness present at all due to the helmholtz resonator. I can also hear the car make pop/gurgle every time I get back on the gas after a shift which is awesome. Definitely go for this muffler if you are going for an "OEM+" sound and want to keep things simple.

-- Francis N., Corona, CA ( MX5 2010 ) August 2021

I know Brian says this thing is louder and with the top down it is, in a good way. It sounds soooooo smooth. With the top up it almost seems quieter. I have the PRHT and I feel like the inside noise is better now. If you are scared to get this because you are afraid it may be too loud put your fears aside. It is just right. Just for reference my wife calls this car my mid-life crisis car so it safe for those of us with some gray in our beards.

-- Justin F., Houston, TX ( MX5 2007 PRHT ) June 2021

Excellent upgrade from stock, no droning/booming, and the occasional pleasant pops and burbles when shifting. I commute 60 miles daily (helmholtz race muffler, stock header, and midpipe) and I think it is very livable. Highly recommended if you're looking for something 10-20% louder than stock at cruising speeds. The sound is so pleasant, I didn't even install the baffle (sold separately) I got with it. The best part about this muffler is It's quiet when you want it to be and only picks up volume when you punch it!

-- Khanh L., Washington, D.C. ( 2012 MX-5 ) April 2021

This exhaust is amazing. Coming from an all stock exhaust to this has completely changed the driving sound, it is much deeper and pleasant to the ear. It is also a good amount louder, but is not intrusive at all. Thanks to the helmholtz chamber, the inside of the car actually sounds quieter than stock at around 2-3k rpms when you are decelerating. In daily driving, the exhaust is subtle and you only notice the deeper tone. When you floor it, it screams and in my opinion, this is perfect.

-- Adam Z., SF Bay Area ( 2006 NC1 ) July 2020

Fit and finish are perfect. Took about 10-15min to install. My car is all stock besides this muffler and suspension the change in sound is great. It Is not too loud at all and there is zero drone even at freeway speeds. The only thing I would change is to add a rolled tip for appearance reasons, but being a race muffler it would cut down on the weight savings. Huge difference from the stock muffler and highly recommend to anyone looking for a great flowing exhaust with no drone.

-- Sean F., Temecula,ca ( 2010 prht ) November 2019