500 horsepower Audi RS5 by Senner Tuning
03/01/2011 14:13 - Worldcarfans: Tuners
German tuner dials output up to 506 PS (372 kW / 499 bhp) and 478 Nm (353 lb-ft) from the series 450 PS (331 kW / 444 bhp). Senner also adds a Bilstein suspension kit and 20-inch wheels.

Source: Worldcarfans: Tuners
http://www.tuning-links.com/news_892_500+horsepower+Audi+RS5+by+Senner+Tuning.html