Wheels: Sizes of wheels that will fit an A2 (non 3l! - the 3L was not sold in the UK and therefore not covered here) Widths and diameters 5.5 - 7J, 15, 16, 17, 18". 7.5J works for some, not for others. Check for signs of argument on the wheelarch liners. 8J is really pushing it and frequently...
I am running 7x16"ET35 without problems. I also run 7,5x16" ET37 and there was some rubbing with brake pad sensor wiring (partly due to incorect routing) so 7x16" ET40 will be really simillar. Clearance to the undercarriage or coilover is fine even with -25mm sport susp