I have a B7 3.0 TDI Avant, calipers are the same as the B7 S4 I also spotted them on a 56 plate 2.7 A6 Avant today but the A6 had much larger discs. Obviously I could not start attempting to measure some other guys discs on Tesco's car park.
Looking at the S4 I think the discs are 345mm and I am going to hazzard a guess that the ones I saw on the A6 were also 345mm.
What hardware do I need to convert?? (Discs obviously)