RoadsterSport 3 Polished Stainless Steel Miata Exhaust Muffler for Miata 1999-2005
View #1 11-1004
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RoadsterSport 3 Polished Stainless Steel Miata Exhaust Muffler


PART NUMBER: 11-1004


Reg. Price: $688.85

Sale Price: $499.00



Free shipping offers apply only to destinations within US Lower 48.

Reg. Price: $688.85

Sale Price: $499.00



Free shipping offers apply only to destinations within US Lower 48.


This Miata exhaust muffler has been a customer top choice for many years. Deep mellow tones flow from our favorite Miata exhaust muffler choice...and this Miata exhaust muffler is the ONLY 99-05 Miata exhaust with an optional highflow midpipe with built in converter and resonator (sold separately) AND adjustable sound level! YES, fits manual and automatic transmission

Built in solid 304 stainless steel and completely polished to a mirror finish, this high quality Miata exhaust is our only choice that incorporates a baffle insert that gives YOU some control over the final sound level (baffle in is only about 15% more sound than stock, baffle out is about 25% more sound than you always have a choice for those longer trips). Weight is just 18 pounds (lighter than factory).

For those that want even more sound add our highflow Miata midpipe for more flow and another 10% more sound. This new version of our best selling Miata exhaust has both baffle included and a double walled tip for years of lasting good looks while giving you control over whether the final sound level.

And, you always have the option of our packed baffles which are sold here separately. Our use of special high density packing materials and a higher perforation rate in the straight through core than most Miata exhaust makers allows us to save more weight over the factory Miata muffler than other choices while still giving you the most mellow sound. For even more flow and sound check out the optional Miata performance midpipe by searching "midpipe" or see it in the list of choices on our Miata exhaust page (paricularly good choice for turbo and full race users).

Install is awfully simple. Disconnect the two nuts/bolts connecting muffler to midpipe. Use dish soap on old stock muffler rubber hangers to get them to slide off. Ideally have exhaust hanger removal wrench handy to make getting the rubber hangers off even easier (even Home Depot now sells them for about 20 bucks). Revers those steps to install the new muffler. Tighten nuts to 30 ft/lbs

Brian's Application Notes: Folks ask us all the time to rank our Miata exhaust choices in terms of sound level. This RoadsterSport Miata exhaust and the Racing Beat single and dual tip Miata exhausts are the most quiet of the aftermarket choices. When used without the removeable baffle our RoadsterSport Miata muffler has as much as 25% more sound than the stock Miata muffler at full throttle, yet just about 10-15% more at cruise. This RoadsterSport has a little more flow than the Racing Beat Miata exhaust due to the 2.5 inch size of the tubing on this choice versus a 2.375-inch tubing on the Racing Beat (both straight-Flow internal designs). The slightly larger tubing of the RoadsterSport Miata muffler also means a slightly deeper tone and a little more burble on decel. LIFETIME WARRANTY. YES, includes gasket and hardware needed for install.

MORE Sound Files at our Exhaust Blog---CLICK HERE TO LISTEN AND READ MORE



Customer Reviews

RoadsterSport 3 Polished Stainless Steel Miata Exhaust Muffler

I bought this muffler and matching mid pipe for my car, which has a FM stage 1 turbo system. I made the purchase because this set up has the largest tubing of any exhaust I could find on the market. In the past, I had used a 2.25" cat back with resonator, and it was too quiet once I added the turbo. This RS3 exhaust sounds great with the turbo. Not loud or quiet, but like a proper sports car. My turbo uses washers between the waste gate actuator and the turbo housing to set boost level. I took 2 washers out (on each side) before driving my car with the new exhaust, since reducing back pressure can yield higher boost levels. The car still hits 8psi. I would call that indirect proof that this cat back flows better than my old 2.25" unit. This cat back does not clunk against the bracing or differential, even without using hose clamps on the muffler hangers. In terms of smoothing transitions where the sections bolt together, there were no gross deficiencies, though I did touch them up a bit. I also spent a little time taking sharp edges off the flanges with a file. Overall, I am impressed with this unit and I would recommend it to anyone with a similar build.

I bought the RS3 muffler to go with the Flyin' Miata 2.5in midpipe on my MP62 supercharged 2004 Miata. My first impressions were that the fit and finish of the RS3 are awesome, it is shiny, the welds look good, and the tip is beefy without being too big. I thought the tone was awesome too, it's of a much lower frequency than the stock muffler. Unfortunately it was too loud for me at anything over 3,000 RPM, and I had an annoying drone in the high 2,000's and low 3,000's -- and this was with the included baffle. I'm sure this could be because I'm using the 2.5in midpipe or the supercharger, and I assume it would be much quieter with the stock midpipe.

After running the RS3 for a few weeks, I ordered the packed baffle and all my problems were solved. The drone was eliminated and the sound level was reduced to a little more than stock. I'm really happy with the RS3 + packed baffle, it still has a similar tone, and still burbles on decel, but it doesn't seem to drone at any RPM. It sounds really good without being loud.

Last winter I bought a beautiful one owner, low mileage, Midnight Blue Mica 2001LS, from San Diego. Only thing not perfect about it was the factory muffler, a little quieter than a Prius! Looked at all the available mufflers and quickly decided on the RS-3 that I had for many years on my 1990. Typically Goodwin, a thing of beauty with quick delivery, outstanding packaging and easy install.

On my 1990,(a cat back) it had a sharp voice, with a great burble and I generally ran the packed baffle to tone it down for my mostly urban driving. With the 2001, (an axle back) with no baffle it is still quieter than the 1990 RS-3. For my mostly urban driving, I'm running the unpacked baffle. It has a little burble on decel and a nice bark on hard accel but is still quieter than the 1990. I suspect that this is due to still running the factory cat and mid-pipe.

After 3000 miles of break in, I feel that it has now reached its optimal condition and I'm very happy with it. Just enough mellow sporty sound without being obnoxious. At cruise there still is a very faint drone but I can eliminate it with the packed baffle.

Looks and sounds great! Deep and mellow and none of the annoying rasp common with 4 cylinder engines. Makes enough noise to be fun without waking up the neighbors. Makes a fun "pop" and deceleration burble occasionally. I'm excited to put some miles on it during the warmer months! Mine is paired with the headers and midpipe from Goodwin as well. Awesome combo

Had this installed by Rocky's Miatamotive, next door to Goodwin Racing, at the same time as Rocky installed my new CSF 42MM Radiator, also purchased from Goodwin.

The OEM hoses were not in horrible shape but made sense to upgrade to these Silicone hoses since I was having the higher performance radiator insalled. Got them in blue, they look great and I have every confidence they are going to perform well.

Can't beat the convenience of having the Yoda of Miata to work on my car right next to the Yoda's of Miata Performance parts right next door with parts in stock.

Glendale cops don't like my Magnaflow system so I bought the roadstersport muffler because of its adjustability and because I knew it would complement my roadstersport midpipe nicely.

It comes well packaged in the box and looks great on the car. The tip is smaller than the Magnaflow I had, but the piping of the system is bigger overall, so at least there isn't that awkward transition from 2.25 inch piping to a 4 inch tip like on the Magnaflow system. The rolled tip is a nice touch too; makes it look like a really high quality stock part.

I started the car a went for a test drive with the baffle in. The car was a lot quieter. I started to miss my Magnaflow. I went home and unbolted the baffle near the tip and went for another drive. This brought some of the roar back, so I left the baffle off. Set up like this with no baffle and my matching roadstersport midpipe, my car is loud, yet refined. There is no rice at startup like there used to be and there is practically no drone on the highway. It still sounds great in tunnels and I got complemented on the tone from a guy in a modified FR-S the same day I put it in. There seems to be a bit of a seat-of-the-pants improvement in power as well. Overall a great system.

Purchased this muffler after researching mufflers on the internet, listening to sound bites, and speaking with Sean. I was looking for something to increase the exhaust sound, but not be obtrusive.

Shipped quickly and on time.

Unit arrived well packed and very shiny. Really nice muffler.

Blocked front wheels, jacked up and blocked rear of vehicle, and dropped old muffler the night before the new one was scheduled to be delivered. Used a spray bottle with Dawn dish detergent and water to lubricate rubber bushings. Slip a screwdriver in between hanger and rubber bushing, careful not to tear, and squirt solution in gap. Did this all by myself in 30 minutes.

New muffler arrived and it only took 15 minutes to install. Use packing material to support muffler under hangers, lubricate rubber bushings with Dawn solution, slip hangers through rubber bushings, put gasket over bolts, put on nuts, and tighten alternating between bolts.

Funny thing happened. Fired her up, stepped on the gas, and was surprised that it didn't sound much different then my stock muffler. Took it for a drive down the road, same thing. Well, the unit is shipped with the baffle installed, which I thought was an extra add on. The glass packed baffle is an add on, the regular units are all shipped with a baffle.

Anyhow, took the baffle out, and was pleased to hear a nice sound, not too loud, not too quiet. Just about what I wanted.

Do not be afraid to deal with Good-Win-Racing. They are top notch and very nice to work with.

Glen Washburn

Fast delivery and securely packaged.
The exhaust was well built and easy to install.
The exhaust tone is deep and throaty during heavy throttle. I like the fact that it is not ricey....
The exhaust not is fine during long trips. I have never drove it with the baffle installed. I'm sure it is quitter, but I am happy with it removed.

Excellent muffler/axleback. Unfortunately for me I picked this up the hard way and ended up spending more money by buying a generic muffler thinking I'd be satisfied with something cheap. So 300 dollars turned into over 400 but lesson learned, do it once, do it right. The RS3 muffler has the perfect tone and fitment is spot on. Pick up the glass packed baffle at the same time though if you have the midpipe as that's a great feature to have different sound levels depending on your use (or mood). I couldn't be happier with the RS3 and wish I just bought this setup from the start.

The RoadsterSport 3 was shipped and delivered within a week of ordering. Just like everything else I've bought from GWR, it was a very speedy delivery.

Installation was a breeze, except for the stubborn rubber flanges. Soap definitely helps.

Here's how the exhaust looked out of the box:

Compared to the shabby stock unit with 90K miles on it:

And, finally, here's how it looked on the car:

I'm happy with the sound, the look, and the price!

Installation was very clearcut and flawless. Sound is excellent. Product finish and looks are top notch. I am very pleased with my choice. Also installed a K&N cold air intake at the same time.

Currently have 100 miles on it and it has just the perfect sound that i expected.
Shipping was lightning-fast and installation was quick and easy. I was worried about having ricey civic-fart noise, but this exhaust has deep, good quality sound. Getting daily compliments and having fun in it. (removing baffle makes the sound wa---y better:))

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