DaytonaB9

Has anyone figured out the logic behind the exhaust valve actuation? Do they open based on throttle load, rpm, and/or drive mode?

Bobby Kinstle

No but I wish Audi would pubish more tech articles like that for car nerds like us.

Also I wish it would rotate the open tips so they all blacken more evenly.

HCGxKaLiBeR

Depend on the drive mode and rpm. Valves open the following order:

The one on the very right side. Then both on the right side. Then all four open on both sides.


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stanj

^^ That. Drives me nuts. First world problems, I know.

dbuxton13

My tips all look evenly blackened between washes, because I only use either Dynamic or Individual with exhaust set to dynamic. The far right pipe runs solo on startup, but the others open up shortly after.

Mr.Meme Yo Girl

i've attached a picture of how the rear section of the exhaust looks like with the valves (the muffler closest to us is the driver side). Basically from what I've read up and have observed, the middle passenger side is open all the time, then the farthest passenger side opens up, then once you're in Dynamic and Sport the bigger driver side valve opens up. Personally before I did my exhaust work, I had unplugged the valves. sounds better and also evens out the blacked tips lol. hope this helps

stanj

Interesting... if the left side opens up only in Dynamic, how come I have black tips on the left as well even though I have exhaust always in Comfort? (I'm a big believer in subtle noise )

mplsbrian

The soil fairy is out to get you Stan!

In all seriousness, the tips do open based on RPM and when you go full ham they'll open regardless of mode (but at a higher RPM in comfort mode iirc). I'm sure the valves also don't exactly perform a perfect airtight seal so that may also help explain some carbon-filled exhaust sneaking past regardless of mode.

Bobby Kinstle

Well that pretty definitively answers that question. Thanks for posting that.