Audi S6 Prestige 450 Horse Power. Super executive sedan. It is amore powerful version of the brand’s everyday A6 sedan. It has been around in its current incarnation since the 2012 model year, having benefited from only a single update last year that brought a bump in horsepower and mild cosmetic tweaks. Every S6 comes standard with Quattro, Audi’s all-wheel-drive system, as well as the A6 lineup’s only twin-turbocharged V-8. (Regular A6s make do with a turbocharged inline-four or a supercharged V-6.) The only visual telltales include trim-specific wheels, aluminum mirror caps, quad exhaust outlets, and a tiny S6 badge in the grille.