Question about Sport Button on RS4

[graeme86]

When you activate the Sport button, it opens up the exhaust flap.

Does it stay open all the time then, or is it still quiet below a certain speed/rpm?

I was reading some roadtest somewhere the other day and they said it was open at idle, but then closed again for the "town speeds" and then opened up again.

That sounds like the stock setting to me.

[PetrolDave]

When you activate the Sport button, it opens up the exhaust flap.

Does it stay open all the time then, or is it still quiet below a certain speed/rpm?

I was reading some roadtest somewhere the other day and they said it was open at idle, but then closed again for the "town speeds" and then opened up again.

That sounds like the stock setting to me.

With Sport off the extra exhaust valves are always closed.

With Sport on the behaviour is more complex:

- at tickover the extra valves are open.

- in 1st, 2nd & 3rd gears the valves close just above tickover and re-open at (IIRC) about 3000rpm.

- in 4th, 5th & 6th gears the valves are always open.

[sidicks]

Presumably this is to comply with EU drive-by noise regulations?!

Sidicks

[graeme86]

Thanks for the clarification. :-)

[Molar]

you can disconnect the pipes to the valves so they are open all the time. Sounds better too. Some have reported that it feels better too. Cant say I noticed but it certainly sounds better at certain points in rev range through being open all the time.