Audi is expected to give us some official word on the upcoming RS version of its ‘5′ range at the 2009 Geneva Motor Show. However, the German automaker recently invited out a couple of press folks at the Ricardo Tormo circuit in Valencia to test drive an ‘EVO’ model of the S5.

The Audi S5 is powered by a 4.2 liter V8 engine producing 354-hp. But this experimental ‘EVO’ S5 was modified to produce a total of 420-hp. The engine was mated to Audi’s new S-Tronic dual-clutch transmission.

Now you might think this is probably just a one-off model but according to InfoMotori, Audi had four models on hand. We’re led to believe that Audi is just testing the waters for a model that will fit between the 354-hp S5 and the upcoming 450-hp RS5 (also rumored to get A 5.2 liter V10 engine that produces 500 horsepower in the Gallardo).

Source: InfoMotori (via MotorAuthority)