Okay, quick question(s), I'm sure I saw a thread on this somewhere, but I can't seem to find it. On an A4 Quattro, can you run wider wheels and tyres on the rear. i.e 8x18's on the front and 9x18's on the back..? I didn't know if this would ruin the 4wd system..? Also is the Quattro system in the A4 the same as a 8L model S3.?