I beat a mod'd Mustang off the line last week. As I accelerated, I saw in the rear view mirror his lights, and what I think may be an unusual amount of exhaust from me. Any experience with anyone who have pushed their RS4 in such a way? The exhaust was not billowing, but I could see it as I sped away. Any response is gratefully appreciated.

normal, big V8 swallowing as much gas as it can gets its hands on to deliever WOT power....youre gonna see smoke

yea, there's a grip of gas going through the engine at wot...

it might also pull a degree of timing, so the gas might not be fully burnt when it exits the tailpipe...

eitherway, unless you notice a CEL, ur good...

That was dust you saw.