Yep, that's the original quattro, the S2/S4 was its successor.
What I meant was its the only S car (except the S1 which was the SWB sport quattro) that used the same layout, ie five cylinder turbo engine 4wd...subsequent S cars had even number cylindered engines...not the same at all...a bit like long hoods and short hoods....
Seriously tho the refinement present in the later cars means the earlier ones, especially the RS2 are gaining a real following in the Audi crowd....