Anyone removed the stock exhaust backboxes?

[IanH755]

Howdo all, has anyone here either removed the stock exhaust backboxes or got no silencers at all and has any vids or recommendations?

Reason - I'm doing quite a few car events/meets/trips etc over the summer (pretty much 1-2 a week) and the stock exhaust is just too quiet so what I'd like to do is remove the backboxes to unleash more V8/turbo noise (no extra power I realise) and fit a straight through pipe from just behind the resonators (keeping them to reduce drone at motorway speeds). However, as this is my daily driver I want this to be reversible so I will sleeve the remaining stock exhaust allowing me to swap between either the stock backboxes or the straight through pipes depending on what I'm doing i.e backboxes for mon-fri (and when selling) and then straight through for sat-sun when doing trips.

At present it has stock downpipes with the Cats and Pre-Cats so as this mod is after the lambda's and the diameter isn't changing then I shouldn't need it remapping nor should I gain/lose any torque/power, I hope.

My preferred option would be to fit a milltek full non-res exhaust inc Decat for the sat-sun noise but (and this is a heinous crime I know) I'd want it valved to bring it back to OEM noise levels for mon-fri as I find the non-res milltek can drone badly at motorway speeds and before I spend nearly £2000 inc fitting one I fancy trying the £200 option which just requires a little spannering time instead which I always enjoy.

I "should" be getting it done on Wednesday if it's not back at MRC to sort a sticky cam follower and I'll post up some build pics and vids.

Cheers...............................................Ian

[amanda1]

IIRC bam had a straight through pipe on darth......pm him and ask.

[Nobby]

i have my standard exhausts in the garage if you want me to take photos/measure etc

[bam_bam]

Used to run straight pipe.

GPOMC.



It was unlivable. But hilarious.

GVOMC.

[IanH755]

Wow Bam, that's a bit more extreme than I'm planning! Was it from turbo back, can't see on my phone?

[bam_bam]

Milly 'race' CATless DPs into some scaffolding then finished off with black ceramic tips. Regrets, none.

I've since had large silencers put in with a manual cabin switch back to straight pipe. It's perfect now, IMO.

[Keaney]

Bam you got electric bypass valves?

[bam_bam]

Yes. By Hayward & Scott.

[marc1]

I met a guy the other day with a B6 S4 and he'd had the rear back boxes cut off and straight pipes welded in. It was much louder than stock with more of an angry bark and a bit more rasp. It sounded loud to me and my B6 has a full Milltek with 100 cell sports cats. The RS6 will obviously be more muted than this due to the turbos, but it will still howl.

Get a spare stock exhaust from a forum member or eBay and cut away.

[Keaney]

So bam is yours remapped in bypass mode or with the silencers?

Always wanted bypasses but think I'm gonna wait till a c6

[bam_bam]

Dunno, I don't think it'd make a difference, there are no restrictions. They dyno'd it in both modes, you can find video of it some where on the MRC fb page.

[IanH755]

Just back (pics/vids later), cost £250 which is very good value for the noise increase I feel. It sounds like a proper V8 now with little turbo noise/whistle heard inside and it's changed the whole exhaust "note" too making it much deeper and it now has a great set of pops and bangs on over-run.

Before at 50mph in 4th at 2K rpm the loudest thing was either the blower fan (set to 6) or the tyre noise. Now it's between 1800-2700 rpm that it's a real growl. I'd say that volume wise it's on par with Amanda's Milltek decat + non-res back section, being the only other full system I've heard. It's certainly louder than a just a non-res back section anyway (heard a few). I haven't done any 70+pmh motorway trips to see if it's droney but my initial guess would be Yes I think as any prod of the right pedal at those motorway revs produces a wonderful noise

I ended up going with a quad tips but made the mistake of losing the support bar across the two pipes. I now realise it's to stop the pipes moving apart rather than to support them which is what I thought initially so I'll be going back to have that bracket added. There's a temporary sleeve holding the right pipe together until the 2 new Audi sleeves arrive next week.

As a potential downside I also felt a little "chavy" after the initial giggles had gone as I live in the beautiful Cotswolds near villages full of OAP's giving me anti-social stares as an Audi estate with a stupidly loud exhaust drove by, something I haven't experienced since my Skyline days

TL;DR - Sounds loud, good engine tone and cheaper/louder than a Milltek!

[bam_bam]

You live in the Cotswolds and you drive a 10+ year old car, you are a chav.

[IanH755]

A quick comparison vid with pics - The camera phone footage picks up the bass much MUCH better than the in-car camera does.

[longman h]

Nice video and very informative. That is the kind of noise I want from the 6, something similar to the E39 M5.
I would love the MTM system but can't justify the outlay of 2.5 large.

Where abouts did you get this done?