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 Ur-S4 / Ur-S6
The 'S' prefix letter has signified Audi's sporting high-performance production models since the early 1990s. The S4 was the high-performance version of the Audi 100 saloon, and was known originally as the Audi 100 S4. It featured a 20-valve, 5-cylinder turbocharged engine and quattro permanent four-wheel drive, providing outstanding traction and roadholding in all weathers. Befitting its status at the top of the Audi 100 series, it was luxuriously appointed and featured as standard a lot of equipment that was optional on lesser models. The car was available in saloon/sedan and Avant (estate/wagon) versions.