Its an interesting point actually. There's a very clear differentiation between sport and non-sport setups in the A4 and A6, but the A8 blurs the lines somewhat. The sport platforms only turn up in the D2 in the 01 model year so they must have done earlier ones with either different dampers or springs, or probably both. You may get the same effect using the springs from an 01-02 sport on a 99-00 sport since the later springs must be slightly shorter to accommodate the higher platform. You can also get a little bit from swapping the rubber buffer thing, although that might be so small as to be invisible.
I'll find out more when I get my 2000 A8 sport in to the workshop and have a good poke around under that
