I've read through various threads that a couple of guys have removed the standard back boxes to allow more noise to come from the slightly too quiet stock exhaust.
Has anyone got any videos please as it may serve as a temporary cheap and quick fix to get more noise. I just don't want to create a drone or chavy noise though.
Thoughts??
Re: Backbox/muffler delete
Posted: Tue Jun 28, 2016 10:45 pm
by IanH755
I did this and, whilst is sounds quite "mid-rangey" (not very deep at all) at low revs and pretty epic at full throttle, during the cold start it is stupidly loud! I mean you if you stand at the back of the you have to shout to be heard over it, not "raise your voice a bit" I mean SHOUT until the revs die off.
It didn't sound "droney" in the way a Non-Res exhaust does but it was so loud it was definitely intrusive at motorway speeds which, TBF, didn't really bother me that much.
So sounds great but stupidly loud at cold start.
Vids - Be aware that my mic is a voice mic and is therefore crap so there's no bass captured making it sound a bit thin and the high volume distorts the sound badly in places (should have done it with a better mic).
Re: Backbox/muffler delete
Posted: Wed Jun 29, 2016 5:59 am
by longman h
Cheers Ian. Perhaps this could be a little crude for my liking.
Re: Backbox/muffler delete
Posted: Wed Jun 29, 2016 12:37 pm
by C6Dia
Im thinking of getting this done too. Theres another guy on the Srs forum thats had this done. Sounded really good.
Does the MRC map need to be tweaked to compensate? Or are performance gains minimal?
Re: Backbox/muffler delete
Posted: Wed Jun 29, 2016 12:44 pm
by IanH755
There's no gains at all, the backpressure is almost entirely made by the two cats and pipe diameter and, as these aren't affected, there was no gain/loss in mine.
The other option you have is Supersprint cat delete pipes but keeping standard system allows better flow plus more non boomy noise. Plus if you want even more noise you could remove centre baffles but still keep end boxes.
Re: Backbox/muffler delete
Posted: Wed Jun 29, 2016 8:45 pm
by longman h
skirs6 wrote:The other option you have is Supersprint cat delete pipes but keeping standard system allows better flow plus more non boomy noise. Plus if you want even more noise you could remove centre baffles but still keep end boxes.
I guess you mean the secondary decat pipes? If so, I've had these replaced with Supersprint pieces instead and it's definitely given the exhaust a little more noise but it needs a bit more.
That's a very good suggestion removing the centre baffles. Are these within the back boxes or before them?
Thanks.
Re: Backbox/muffler delete
Posted: Thu Jun 30, 2016 2:37 pm
by TomRS
My first RS was straight through barring the tiny rear silencers... sounded great imo.
My second one had a milltek already on it, and secondary decat, it sounds pretty rubbish! i really need to get a different exaust im looking down the inconel route in 3"
Re: Backbox/muffler delete
Posted: Mon Jul 04, 2016 10:16 pm
by longman h
So I've asked 'Paul the Welder' to pop over when he's next free which is the beginning of August, to open up the backbox and modify the stock baffles etc in order to free up some more noise.
For those that don't know or haven't heard of Paul, he's basically the guy all the BMW owners use to modify their stock exhausts, especially within the E92 crowd.
Once it's been done, I'll post up some more info and videos.
Re: Backbox/muffler delete
Posted: Tue Jul 05, 2016 1:48 am
by IanH755
Just seen this and had to LOL at the price - £900 for a back-box removal when mine only cost me £300 at MIJ Exhausts -
I had a full custom MIJ exhaust made for my old B7 S4 (downpipes, cats and all the way back). It sounded OK on full chat but droned despite me stating as the whole basis for the design was that I didn’t want it to drone. Worse than that though in MRC’s opinion it was what was restricting the power on the rolling road meaning it made less power with the S2 remap, filters and exhaust than it did stock. In short it was a lot of money for worse than no gain, and a lesson learnt never to touch MIJ with a barge pole!
Re: Backbox/muffler delete
Posted: Tue Jul 05, 2016 4:00 pm
by IanH755
*off topic MIJ* - For what I had done they were fine and while I was there there was a C5 RS6 in for a Cat-Back and his looked good too (smooth welds, good bends etc) but both jobs very pretty straight forward whereas making a good set of downpipes is much more difficult and I'm not sure I'd trust them with that bit TBF.
Re: Backbox/muffler delete
Posted: Tue Jul 05, 2016 4:16 pm
by R33
To be fair the exhaust looked fantastic, great smooth welds, it looked like it should flow better than the standard exhaust, the tips looked great, like standard just a little bigger. It just didn’t work though, so for circa £1000 a bit of a waste of money. Hey ho it was a long time ago now.