With the Frankfurt Motor Show just around the corner, Audi is wrapping up development on the S7.

Caught near the Nürburgring, the prototype features an aggressive front fascia, aerodynamic side skirts and a four-tailpipe exhaust system. Other goodies will likely include a sport-tuned suspension, a high-performance braking system and faux aluminum mirror casings.

Power is expected to be provided by a turbocharged 4.0-liter V8 engine that will also be shared with the Bentley Continental GT. Performance specifications are unknown at the moment, but the engine should produce at least 435 PS (320 kW / 429 hp).