Audi Ur-S4 / Ur-S6
The Ur-S4 was produced from 1991 to 1994, while the Ur-S6 was produced from 1995 to 1997. They both featured a 2.2 litre, 5-cylinder engine with turbocharging and an intercooler, with of torque. In Europe, V8-powered versions of both S4 and S6 were available. The S4 version sported a engine (the same "ABH" engine as in Audi V8), the S6 had an upgraded engine "AEC" with . American versions featured a 5-speed manual transmission and in Europe a 6-speed, as well as a 4-speed automatic transmission could be substituted.
Audi S6
In late 1997, Audi introduced an all-new range of Audi A6 models, based on the Volkswagen Group C5 platform. A new Audi S6, now officially known as the Audi S6 quattro appeared in 1999, to complement its A6 platform-mate. It was available in a four-door saloon/sedan and a five-door Avant (estate/wagon). In North America, the Avant bodystyle was the only version available. The vehicle could accelerate from standstill to in 5.7 seconds, and from 0 to in 21.7 seconds. The top speed was electronically governed to .