Despite the rumors of its demise, the next-generation Audi RS4 appears to be on track (literally) based on this mule that our spy shooters have just spied on Germany's Nürburgring. Seen here testing in the all-too-desirable Avant body style, the next RS4's final design will likely be a bit more aggressive, incorporating a much more pronounced front fascia complete with lower air intakes similar to those on the RS5 Coupe. On this mule, we can clearly see the larger wheels (straight from the RS5 – how 'bout that), bigger brakes and slightly wider track.
As for power, the safest bet is to expect that the RS5's high-revving 4.2-liter V8 will carry over to the RS4, producing somewhere around 450 horsepower. Other rumors have suggested that an all-new 4.0-liter twin-turbo V8 could be put to use here, but based on all of the scuttlebutt we've heard, the 4.2-liter V8 still looks to be the safest bet. Since the RS4's key competitors will be the BMW M3 and Mercedes-Benz C63 AMG, Audi would probably be wise to use the 450-hp mill in an effort to keep things as competitive as possible. The RS4 will surely be no slouch, and we're bursting with eagerness to see (and drive) the end result.