Is it normal for our exhaust burble to sound real metallic? It's almost like someone it tapping on the muffler with a hammer under decelleration. Is this normal for a factory exhaust with 2000 miles? Is this why people change their exhaust? Or will it sound less metallic as the carbon deposits build up inside the mufflers? (sorry for all the questions)

 

I think it's supposed to sound that way. It's a sound the old Minis make. I absolutely love it. Sometimes I kind of tap the gas just a bit while decelerating to get more popping. I don't know how other people feel about it or whether the after-market exhausts eliminate it or accentuate it, but I LOVE IT. Did I mention I LUUUUUUUV it.

 

It's hard to describe a sound, but my 06 MCS with less than 2k miles definitely makes popping sounds on deacceleration. I love it. My brother said it sounds like there are holes in the muffler.

My 03 MCS was quiet. I like the new one better. Snap, crackle and pop!

regards,
Red

 

Read it all here:
http://motoringfile.com/2005/06/28/exhaust_popping/

 

I'm not going to take the time to read all of the article, just make a quick statement...

I have a MCSa and my exhaust never "crackled"... I just recently installed (or should I say my boyfriend did, thanks babe!!) and I actually have a crackle!! Man am I stoked!! I give it gas all the time, just so I can here it!! I LOVE IT!!

 

After my above post, I went to pick up my son from the movie (hence listening to my car ), and was thinking about mitchman's use of the word "metallic" . I would not describe the popping sound as metallic at all , so maybe something isn't right, mitchman. I was thinking maybe there is something loose right near where the popping sound is coming from, and maybe that is what is giving your pop its "metallic" nature.

 

the popping coming from the exhaust is when unburned gas in deacceleration hits the very hot cats and ignite it happens on alot of cars my ole 92 ranger did it alot... when ppl change there exhaust they just want the car louder and deeper but most have the same or more poppin... i also heard somewhere that the mini's ecu is programmed to throw a lil gas to cause it to "pop" more

 

I've had my car since Feb 06. Enjoyed my "burble" when I got it. During the hot Florida summer, my burble seemd to go away. Now it's starting to cool down and my burble is back (Wehoo!!).

But for the past 4 days I now have a metallic harse cracking sound to my burble. Not the mellow throaty burble of before.

Does anyone have any input on that?

 

On my 05 MCS, I hated what I described as the "tinny" pop pop pop so much that I got the Milltek catback which I loved for its throaty burble. I was embarrassed to drive thru parking lots having people turn to look at this new car with the exhaust that sounded like it had some loose metal rattling around in it. Not after the Milltek. It sounded awesome. With my 06 JCW, its been noo problem. Not as throaty as the Milltek but enough to keep me from having to drop another $695.

 

The "popping" on deceleration is a dead giveaway that the fuel mixture is a little too lean. It's very common on newer motorcycles as well.

Some cars and bikes are mapped very lean from the factory in order to pass emissions standards. Since the emissions from the MINI engine are higher-than-average to begin with, I'm not surprised that this would be the case.

When you decelerate, the air/fuel mixture leans out enough that you don't get complete combustion in the cylinder, so some of the fuel remains unburned until it gets into the exhaust system.

Running lean under heavy throttle is bad for the engine and will eventually damage the pistons, but a lean condition upon deceleration isn't dangerous, since the engine is not under any great load and the dynamic cylinder pressure is low at that point.

BMW published a technical bulletin letting dealers know that the pop/burble is normal, and not to try to "fix" it. They also advised that the burble "feature" can NOT be added to pre-'05 cars! (I guess they've had owners come in asking to have the burble added to their cars).

Scott

 

Don't get me wrong.....I like the burble (backfire). It makes the car sound very performance oriented. I just don't like how "tinny" it sounds. Like it is backfiring into an empty tin trash can.

I'll try and make a recording this weekend so you all can hear it. I just want to make sure nothing is wrong......although I'm going to be replacing the mufflers anyway for the 2007 autocross season.

 

I agree with you I love the sound of it!!!

 

My OEM exhaust's pop definitely changed over the first 4000 miles. Biggest change came when I had my ECU reflashed, absolutely more metallic.

My JCW exhaust has a more refined sound that appears to be getting deeper with time.

 

One way to get real burble on an earlier MINI (meaning, not the ECU generated kind) is to install an aftermarket exhaust. most tend to burble, I guess because of less backpressure due to larger pipes. Burble is definitely addictive!

 

If you're talking about the regular burble... yum! My 03MCS has gotten fantastically burbly over his 67K.

If, as you say, it is "tinny", might I suggest you check the muffler brackets. Mine started to sound tinny a few months ago and it was because one bracket had completely rusted through and broken, and the other was well on its way, thus causing metal-on-metal vibration as the muffler rattled. This shouldn't be an issue (I wouldn't think) on a car with only 2K, but I'd check nonetheless. It's the only thing I can think of that would make it sound metallic.

 

It's "tinny"(not meaning to be argumentative), e.g.: We have our 04 MCS. No significant burble, no tin. When I went to test drive an 05, I drove off the lot, heard a tinny pop pop pop on decel and I didn't make it a half block before I turned around to report to my MA that something was loose on the exhaust system. I couldn't imagine a new car making a sound like that if something wasn't broke. Of course, he told me it was designed that way, nothing unusual, they all have it(MCS's). Oookay. Didn't think much more of it and when I took delivery of my 05 MCS, there it was, a tinny pop pop pop! While it may be pleasing to some, I hated it and and spent $695 (Milltek) to get rid of it. Now I loved that Milltek burble! Now, my JCW catback is a little quiet but it's sound/burble is good enough such that I don't have to drop another $695 to get rid of an MCS stock exhaust system which sounds.....tinny!