I've got the 2.0 TDi 140 and it's on the ST3 race map. Even though I think it's pretty nippy, I don't think it would keep up with a standard 8l S3. Think the TDi would have a little bit of chance mid range, other than that the S3 would pull away.
I've tried to record some 30 - 70 times and I seem to cover it in about 6 secs, not quite sure how accurate it was as there was 2 people in the car and the timings were done on a phone lol.