The A6’s rivals include the BMW 5 Series ... wringing an additional 30 hp from its twin-turbo 4.0-liter V-8, bringing output to 621 hp. Other changes to the RS 6 include reduced sound-deadening ...

However, Audi engineers also built a 621 HP twin-turbo V8 for the diminishing Audi RS6 sports wagon. But, as we look towards ...

The A6’s rivals include the BMW 5 Series ... seven-speed automatic transmission and standard all-wheel drive. A 335-hp, mild-hybrid 3.0-liter V-6 is optional. If you’re a car shopper with ...