Exhaust sound query

Hi all, Does anyone have experience of the replacement exhaust available from MX parts as follows prod no. [SI3144] to a 2ltr 2011 roadster model. It’s just under £300, so a reasonable cost. I’m looking for something that has a little more burble than the factory one, but not too silly as I’m in my 60’s so will obviously get a few comments, even from the grandchildren :grin:. If anyone has experience, photos of one fitted, and recording of sounds it would be very much appreciated.
Thanks and enjoy the current sunshine.

I think you mean part S13145 @£285, if so I can comment on that one.
I fitted one around that price, it looks exactly as in that listing but could have changed since, who knows.
Anyways my experience it droned badly, so much so myself and particularly my wife couldn’t stand it any longer, after around 12 months I removed it.
Now have a Cobalt, different again, sporty tone but doesn’t drone, happy.:+1: It’s been on over 3 years, purchased from Moss Europe.
Others that Mx5parts sell could well be ideal, I have no knowledge to pass on about those, just the particular one you mention. Others can comment further on back boxes I’m sure.:+1:

I think that Mick is right - summarising all the various exhaust posts that have been on this forum (for a variety of MX5’s) would support exactly this view - if you want a sporty exhaust that doesn’t drone, is not too loud or pop and bang - get a Cobalt (from Moss). I am sure there are others, but there have been only positive reports on the Cobalt.

I was looking for one for my Mk1, but they have stopped doing the single exit ones and now only seem to do a twin outlet one, which is not what I want…

I’m in my late 50’s, so I don’t want anything that drones either.
Besides it will irritate my tinnitus.

I have the Coablt also.

I find that it doesn’t sound much different at cruising speeds, but adds a nice sporty note at street speeds.
I do have a little drone when driving through my estate though, say 2nd gear at 20mph, but not so bad that it makes my ears bleed.

I have a Cobalt Cat Back on my Eunos and a Cobalt rear box on my Mk4. Lovely sound and it won’t p*ss your neighbours off but you will enjoy the slightly better exhaust note. Don’t know if your car has a sound tube, but I deleted my Mk4 one to get rid of the piped lift musak and I can hear the exhaust note unaccompanied with anything else.

I had my bro-in-law drive my Eunos in front of me in a long tunnel - wow, it sounds even better from behind! Highly recommended as far as I am concerned.

I’m 62 and have a Cobalt back box fitted ( 1.8 MK3 ) I’m very pleased with it, looks good sounds sporty but not too loud, and after a few hundred miles I assume it soots up a bit and the sound settles to a nice deeper sporty sound , without being obtrusive, but ideally you might want to hear one first , in the flesh so to speak.


Hi all, Thanks for such a quick response. Looks like consensus is Cobalt, but having looked on internet it appears they are changing it and have none in stock. May have to wait and see if anyone has one, or find one elsewhere. Perhaps someone knows where one is available. Does anyone know what the new cost was?

I believe they were just under £300 for the back box…

Rob, name the nearest town to where you live and maybe someone local to could give you a listen. May have to be roadside or following in the current circumstances!


Good call, it’s Aldershot, but could easily meet within 20 miles or so.

Rob, I live near J12 of the M4 which is about 20 miles from you. I have a Cobalt rear box fitted to a 2010 2ltr NC. You are welcome to have a listen. Will pm you.