Trying to understand the OEM sport exhaust 2016 S7

[Tnmax]

Got a question, but I don't want to rehash the many, many, exhaust mods/after-market exhaust posts from over the years. I've decided on a cat-back system for my 2016 S7 with sport exhaust, but in doing my research from all the various posts, I've come across a few references that state that my drivers side muffler is different from the passenger side muffler. Why would this be? Can anyone explain how the exhaust is routed through each in quiet mode and sport (dynamic) mode? See pick of the OEM set up. The valves are clearly in different locations. Sorry if it's been explained before and thanks for any insight.

[gk1]

Unfortunately I don't know much about the specifics of the sport exhaust, and I'm not sure anyone has cut one open to get specifics.
Based on readings I feel I understand how the standard exhaust works. If the sport exhaust is the same just with the valve re-located I don't know for sure.

The standard exhaust comes into the muffler like seen here.


During MOST operations on the standard exhaust the valves are OPEN. (They basically only close for 4-cylinder operation.) and most of the extra "performance" noise is created by the soundaktor.
You can see the exhaust comes in one pipe and has two options to flow out. The long skinny pipe which is open all the time or the fatter short pipe with the valve on it. So that is fine and perhaps understandable. MOST of the time in V8 operation the valve is open and exhaust flows out all pipes, then in 4-cylinder mode the valves close altering the sound characteristic in a way to avoid (Audi term) "buzzy" noises from 4-cylinder operations. Coupled with ANC and active motor mounts to eliminate any unwanted noises/vibrations.

Now on the sport exhaust as you know the one valve is moved so if it is closed it blocks the entire driver's side muffler. If the valve is closed exhaust gasses for that bank would have to cross-over in the suitcase resonator to the passenger's side. (I honestly don't know what would happen if you remove the suitcase for straight-pipes without putting in a suitable crossover. Probably not good.) IIRC the valve is closed at idle on the sport exhaust as some I have read some say steam only comes out the passenger's side on cold days. This contradicts the standard exhaust operation as the valves are open at idle on the standard exhaust.

Standard exhaust operation from testing by another member:
4 Cylinder Mode - Exhaust flaps are always closed when the engine is running in the 4 cylinder mode, regardless of whether the exhaust is set to comfort or dynamic.

Parked/Low Speed - Exhaust flaps are always open when the car is stopped or the car is running slow, regardless of whether the exhaust setting is comfort or dynamic.

Dynamic Mode - While I did not do complete testing in every possible situation, it seems like the exhaust flaps are always open when in the dynamic mode, unless the engine is in the 4 cylinder mode.

Comfort Mode - The exhaust flaps move to the closed position at around 65 to 77 Km/hour. When the flaps are closed and the car is coasting to a stop, the flaps open around 25 Km/hour. [Vag-Com displays the units in Km/hour, not mph]

So question still remains, how exactly does the sport exhaust operate?
Safe to say in V8 mode under acceleration both valves would be open. (Does one or both close briefly on upshift to give the fart noise?)
In 4-cylinder mode is just the driver's side valve closed? I doubt so as I think they are not interdependently controlled valves. Either both are open or both are closed. (I could be wrong.) But any way you slice it at least one of the valves has to close in 4-cylinder mode.
Are the muffler internals of the sport exhaust the same as the standard exhaust?
AFAIK the pops and crackles of the sport exhaust are actually programmed into the ECU and have nothing to do with the sport exhaust itself.
Hoping someone else can chime in with more info.

[A6sport]

That looks like my exhaust!


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[A6sport]

But here’s the thing, the left and right sides are different (left & right sides are not interchangeable) when in dynamic mode the valves in then resonators are open and is more aggressive.


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[A6sport]

But here’s the thing, the left and right sides are different (left & right sides are not interchangeable) when in dynamic mode the valves in then resonators are open and is more aggressive.


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This is my exhaust, really.


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[07S6]

From what i understand, on a Sports exhaust, the difference is that the left muffler is more of a straight-through design (and louder). And, with that set up, the left side valve is located before the entire muffler and when that closes, it seals off the entire left muffler - forcing the gases to cross-over to the right side only via the center suitcase resonator.

[A6sport]

From what i understand, on a Sports exhaust, the difference is that the left muffler is more of a straight-through design (and louder). And, with that set up, the left side valve is located before the entire muffler and when that closes, it seals off the entire left muffler - forcing the gases to cross-over to the right side only via the center suitcase resonator.

Yes, my old friend, that 's what I was trying to say I think...lol

[09S5]

Close up



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[Audisthesia]

I can confirm pops/crackles are an ECU thing and have nothing to do with valve position. I also can confirm valves operate together, never independently. Aside from that, gk1 nailed sport exhaust valve operation.

[skhan91]

All I am kind of stumped here but wondering if anyone can help:

My 2016 S6 has the sport diff and the exhaust has the valves in the two different places (drivers side has valve before entire muffler while passenger side has valve at the tip only). However, my exhaust tips are chrome and the sound definitely does not sound like it’s a sport exhaust as it’s quiet compared to what I’ve heard online.

Any thoughts?

[joserod92]

All I am kind of stumped here but wondering if anyone can help:

My 2016 S6 has the sport diff and the exhaust has the valves in the two different places (drivers side has valve before entire muffler while passenger side has valve at the tip only). However, my exhaust tips are chrome and the sound definitely does not sound like it’s a sport exhaust as it’s quiet compared to what I’ve heard online.

Any thoughts?

Same here.

[gk1]

Perhaps sport exhaust was not a thing in your respective countries CA and DR ?
Some strange regulation maybe?

[joserod92]

Perhaps sport exhaust was not a thing in your respective countries CA and DR ?
Some strange regulation maybe?

I really have no way of knowing, but it is strange that my car has the sport diff and no sport exhaust, also I haven't seen any c7.5 here that has the black tips.

[ndabunka]

I really have no way of knowing, but it is strange that my car has the sport diff and no sport exhaust, also I haven't seen any c7.5 here that has the black tips.

My C7.5 2016 S7 has the sport diff and the black exhaust tips but I also have the black trim package so not certain that provides any illumination on this subject?

[Alabama]

All I am kind of stumped here but wondering if anyone can help:

My 2016 S6 has the sport diff and the exhaust has the valves in the two different places (drivers side has valve before entire muffler while passenger side has valve at the tip only). However, my exhaust tips are chrome and the sound definitely does not sound like it’s a sport exhaust as it’s quiet compared to what I’ve heard online.

Any thoughts?

Are you first owner? Did it come that way from the factory, or did someone work on it over the years?

[TexasDfwS4]

Mine has the black tips as well.

[skhan91]

Are you first owner? Did it come that way from the factory, or did someone work on it over the years?

I’m the second owner but everything completely stock on it. No signs or history of mods and all parts are OEM. Came this way from factory from what I can tell. It has the black optics trim package as well


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[joserod92]

I’m the second owner but everything completely stock on it. No signs or history of mods and all parts are OEM. Came this way from factory from what I can tell. It has the black optics trim package as well


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Interesting.

[09S5]

Sport exhaust

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[Audisthesia]

I really have no way of knowing, but it is strange that my car has the sport diff and no sport exhaust, also I haven't seen any c7.5 here that has the black tips.

My C7.5 also has the black tips, MY2018.

[Alabama]

My 2016 S6 has the sport diff and the exhaust has the valves in the two different places (drivers side has valve before entire muffler while passenger side has valve at the tip only). However, my exhaust tips are chrome and the sound definitely does not sound like it’s a sport exhaust as it’s quiet compared to what I’ve heard online.

Post #19 shows the exhaust tips are mounted separately from the rest of the exhaust, so maybe your chrome tips are a result of a "Monday build" in the factory. My 2014 S6 build sheet only has PR code 0P0, which translates to "Rear exhaust tailpipe (standard)". No separate PR code for the tips, but I don't think there was any exhaust option on the 2014. If you truly believe the sound is not right, maybe you should make sure the valves are actually working properly. There are other AZ threads that speak to this.

[LawDawg]

Post #19 shows the exhaust tips are mounted separately from the rest of the exhaust, so maybe your chrome tips are a result of a "Monday build" in the factory. My 2014 S6 build sheet only has PR code 0P0, which translates to "Rear exhaust tailpipe (standard)". No separate PR code for the tips, but I don't think there was any exhaust option on the 2014. If you truly believe the sound is not right, maybe you should make sure the valves are actually working properly. There are other AZ threads that speak to this.

Post #19 only shows somebody putting aftermarket tips next to sport exhaust tips. The tips on Audi exhausts (std. or sport) are not interchangeable - they're welded as part of the muffler.