Witness this RS6 Avant, powered by a 553-hp, twin-turbo V-8. Car agnostics and busybody neighbors won’t know what you’re packing in your A6 Avant, a wagon usually fitted with a more pedestrian four- or six-banger. The initiated, however, will recognize the RS treatment, which includes wider rear fenders, broad front air intakes, darker head- and taillight reflectors, and—this is important—two large oval exhaust pipes.

Audi is actually using the RS6 Avant to experiment with its overall design language. Thanks to a new rear bumper, the “overbite” of the A6 taillights is gone. And up front, when either of the optional carbon-fiber or aluminum packages is ordered, the bottom portion of the RS6’s large grille is emblazoned with large-type “Quattro” lettering in a framed insert.

As with the precious generation RS6 Avant, which packed 580-hp, twin-turbo 5.0-liter V-10 adopted from the Lamborghini Gallardo, the current RS6′s 553-hp, twin-turbocharged 4.0-liter V-8 produces vicious acceleration at virtually any engine speed, as well as a lusty and aggressive exhaust roar. Even when cruising at or well above triple-digit speeds on the autobahn, a stab of the throttle catapults the 4500-pound wagon forward. Keep your foot in it, and the rush of acceleration doesn’t let up until you’ve maxed out at 155, 174, or a lofty 190 mph, your limit dependent on which governor setting you selected from the extensive RS6 option list. We’re told the wagon has a theoretical unchecked top speed of more than 200 mph.