Milltek Secondary Cat Bypass

Nardo007

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Hey guys has anyone fitted a secondary cat bypass to the standard sports exhaust on an RS3?
Wanted to know if this was bolt on bolt off scenario so I could put the stock set up back in if it was too loud.
 

AudiNutta

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The nardo car on there has the set up you have described, seems to make a big difference.

It is bolt on bolt off, I found the pipes from Miltek on eBay earlier for under £180. 3 bolts on each pipe section (two sections to change), then just a clamp on your existing exhaust I believe.

It looks something that could be done off axel stands if you were determined.
 

AudiNutta

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elton121272

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Seanix

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Miltek makes them for the 8v as well. I have it installed on my car.
makes a noticeable difference but then again I have the sports exhaust.
one thing to keep in mind is that the low rpm pops/bangs will be reduced with the secondary decats. best way to describe it would be muffled. anything below 3000rpm and the oem secondary cats actually sound better as it has a deeper note to it.
but higher in the rpm range, and it sounds raw, louder.

in general, the exhaust is louder.
hope that helps.
cheers.
 

terminator x

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^^ Sports exhaust is plenty imho albeit maybe with decat pipes. I can't believe that a Miltek exhaust can improve on it, certainly any aftermarket ones I've heard on t'internet sound the same or worse.

TX.
 

Hal Adams

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For fear of sounding completely ignorant - how does one know if a car is fitted with a sports exhaust..? And, on the subject, the same for the the 'Dynamic Pack' people refer to..? (is this the switch that opens the exhaust flaps?)
(Forgive me but my car is made for the Czech Republic and I have no idea what is in the spec sheet - other than it meets EU conformity!)
 

terminator x

Registered User
In the UK "dynamic pack" was mag ride + sports exhaust. We couldn't spec the exhaust on its own. The only way to tell if you have the SA is either on the original order or to get the car on a ramp as the left hand bit of the exhaust (near the oval section) has a small pipe that a non-sports doesn't have. This is what releases the sound!

TX.
 

Hal Adams

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Ah, good, I know something more that I did not a moment ago! Thanks!
I do not have mag-ride and have to say the exhaust is not over loud except when flooring it, but will have a look when I do the rear discs.
For what I paid for the car compared to some, I think I have a fairly poverty spec model - the criteria in my purchase was not having a glass roof and this was one of the few in the right colour and interior.
 

Hal Adams

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Indeed!
However, since my last post, I am not sure it is totally poverty spec. Looking at the brochure above, I think the car was built for comfort as it has the B&), SS seats, cruise and auto lights, mirrors etc.
But I see the Mag-ride is 'automatic' unlike my little Mercedes that has a manual switch to activate the feature - so how, on the RS3, do I know if I have Mag-ride..?
 

Hal Adams

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Again, you have all the answers - thanks!
I only have ability to set engine/gearbox, steering and engine sound. So on this basis I do not have mag-ride and I presume not sports exhaust if they go hand in hand. I am not complaining as I am not sure I want any more noise than is there already..!
 

Rocketer

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Depends as in oz all there cars came with sports exhaust as standard and mag ride was an option

In Sweden we had both sport exhaust and magride as an option. They could have atleast done a package of it ):
 

45bvtc

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For fear of sounding completely ignorant - how does one know if a car is fitted with a sports exhaust..? And, on the subject, the same for the the 'Dynamic Pack' people refer to..? (is this the switch that opens the exhaust flaps?)
(Forgive me but my car is made for the Czech Republic and I have no idea what is in the spec sheet - other than it meets EU conformity!)

ALL of the options for your particular vehicle are listed on the identification certificate that's affixed somewhere in the boot space; well mine is anyway. Copy the PR Codes from the certificate into the PR Code Finder (http://prsearch.planetvag.com/) and hey, there's a list of your cars build credentials.

Alternatively, go ask your Audi dealer for a copy of your own vehicles build data: 5-pages of A4 for mine to include both start and end dates of build and details such as 'without trailer hitch' and 'information kit in English'.

I've three Audi cars and non of them purchased from my own Audi dealer but that Audi dealer has supplied me with chapter and verse on each of my cars; just need to ask 'nice' as they've so much information available.

Oh, and I think you'll find ALL RS3s were assembled in the Ingolstadt, Germany, and Győr, Hungary, Audi plants. If you've one made in the Czech Republic then maybe... :shrug:
 
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Hal Adams

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I have a couple of pages that comprises the original spec and CofC, but they are in Czech. I will get them translated and have a look for the id in the boot.
My car was made in Germany yes, but for the Czech market, so it is all a mixture of German, English and Czech.
 

Rocketer

Registered User
Hey guys I am getting the Milltek Secondary Cat Bypass fitted as we speak. Will let you know how it goes!

If you have sport exhaust you are probably happy with it but if you have origin exhaust you gonna hear a difference when you are "opening" exhaust flaps and for a really good result you should do flaps "all the time open" mod which is the nearest you can come without either have a sport or a Milltek catback system.
 

Nardo007

Registered User
Ok... it's strapped on. Very easy job could have done it myself with the ease of a hoist.
Sound wise at first I thought it sounded better stock. It definitely louder with the bypass but sounded meatier at lower revs like idle with the standard Audi sports exhaust.
 

Seanix

Registered User
Yup agree. Very similar to what I described in my previous post above.
It's actually muffled under low revs. Whereas with the oem secondary cats in place, even at low revs the downshifts are meatier.
But overall the sound is louder across the range.
 

RS3ER

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Better off less pops & crackles makes it louder I'm taking my pipes off & putting the cats back on.i had a EML light come on Audi charged me £60 to clear it because of the mod.Told me my warranty void if I keep the pipes on also the DTC kept coming back on when clearing it myself with VCDS & VCP pro
 

Rocketer

Registered User
Hmmm, strange, than its pretty much a lot of non warranty cars driving around because of decats and even Milltek catback should be it also and EBC brakepads, aftermarket airfilter and so on...........I must check it with my Audi service here how they are thinking about these mods.

Although decats changes for instance spool up which is much faster now so a little understanding I have if for ex turbo is damage and I want it as an warranty issue. We can also agree that they are walking away with any warranty issue if they can and even though its on their table to fix it, proven by the brakes where we have full warranty but they denies it as we all know.
 

Seanix

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The exhaust note is nicer but with less pops n crackle at low revs.
Sounds sweet above 3000rpm.
Bit of a trade off, I prefer the stock note at low speeds/rpm.

RS3ER: Audi dealer confirmed the same with me. Basically any mod will effect warranty.
Even a drop in replacement filter voids warranty because it alters the air flow rate. Not sure if all the dealers are consistent with this approach.
 

Rocketer

Registered User
Better off less pops & crackles makes it louder I'm taking my pipes off & putting the cats back on.i had a EML light come on Audi charged me £60 to clear it because of the mod.Told me my warranty void if I keep the pipes on also the DTC kept coming back on when clearing it myself with VCDS & VCP pro

AooN wrote in his thread that EML is not coming on by switching to for instance Milltek decat pipes. I have also done it and no EML so what else have you done or in other hand what was the problem and is it solved now? Good to know if its gonna fault later.
 

RS3ER

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EML wasn't from secondary decats the DTC code was exhaust vacuum valves from my autoscan & no I haven't once disconnected the valves.i got charged for the diagnostic because the tech said it was the pipes what was causing the EML which I know was waffle .reason for my post was honest opinion on the sound & warranty issue I'm not losing my warranty for the sake of £175.i had a goodwill claim last year for a 8P engine cost me £5,300 from the same dealer
 

Scholes

Registered User
EML wasn't from secondary decats the DTC code was exhaust vacuum valves from my autoscan & no I haven't once disconnected the valves.i got charged for the diagnostic because the tech said it was the pipes what was causing the EML which I know was waffle .reason for my post was honest opinion on the sound & warranty issue I'm not losing my warranty for the sake of £175.i had a goodwill claim last year for a 8P engine cost me £5,300 from the same dealer

An 8P 2.5 TFSI engine would be a far bit more than £5.3k from Audi.
 
C

ComputerControlled

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I don't get it when people want to change really nice, well designed cars... sticking this pipe and that pipe on it whilst risking a warranty.
Standard sports exhaust is pretty damn good IMO.
 

RS3ER

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No of course not the secondary bypass pipes won't damage the engine the ECU is none the wiser its nothing to worry about
 
C

ComputerControlled

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That's the human race. Never happy and always wanting more!
You're right, human nature that is.
The key is though, know when you're winning and be happy with what you got:sunglasses:
The stock RS3 is a pretty mean car as it is. Not worth changing little bits round IMO. Unless you're Aoon lol... but that's like a completely different RS3 altogether!
 

RS3ER

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Learn how to read properly before you put up sarcastic posts
 
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