Car and Driver

Overview: No, you're not reading the specifications wrong: This relatively unassuming big German luxury sedan really is a member of the exclusive 600-hp club. The Audi S8 Plus ^[1] competes in the upper echelon of the luxury-sports-sedan realm, trading blows with such machines as the 577-hp Mercedes-AMG S63 ^[2] and the 600-hp BMW Alpina B7 ^[3]. The previous, 520-hp S8 wasn't quite keeping up in the horsepower wars, though, so Audi introduced the top-dog Plus model for 2016 with more power—and it's now the only S8 configuration available to U.S. buyers. (We're not complaining.) Beyond its burlier engine, the S8 also differentiates itself with a shorter, 117.8-inch wheelbase; as with the BMW 7-series and the Mercedes S-class, the regular A8 is long-wheelbase only in America—the A8L in Audi-speak. The Audi also has an uprated chassis, including a stiffer suspension and bigger brakes, as well as a subtle visual makeover with unique styling treatments front and rear and snazzier interior trim.

What's New: Other than a slight price increase for the new model year (up $1025, or less than 1 percent, to $116,850), the only equipment change for the 2017 S8 Plus is a newly available upholstery option: black leather with Arras Red stitching, which costs $5500 as part of an Audi Design full leather package. Due to more rigorous enforcement of EPA coastdown test procedures ^[4], the 2017 S8 Plus loses 1 mpg on its highway and combined fuel-economy estimates, which are now 15/24 mpg city/highway and 18 mpg combined (we averaged 15 mpg in a test of a 2016 version ^[5]).

What We Like: Oh boy, that engine. The S8 Plus's twin-turbocharged 4.0-liter V-8 has a sinister yet subdued rumble and rockets the big all-wheel-drive sedan down the road with supercar-like force. The sprint to 60 mph is dismissed in a scant 3.3 seconds, only 0.4 second behind Audi's own V-10–powered R8 sports car ^[6]. If you shell out $11,000 for the Dynamic package, the S8's top-speed limiter doesn't kick in until a lofty 190 mph—perfect for the autobahn, if not American freeways.

Combined with its subdued exterior design—there's just enough extra visual aggression to make sure you won't be mistaken for an A8 driver—the S8 Plus's blistering performance makes it one of the ultimate sleepers sold today. In Comfort mode, it'll cruise around like the big, cushy luxury sedan that it is. But in Dynamic mode, it hunkers down on its suspension and seemingly defies the laws of physics with keen steering, deft responses, and a willingness to rotate that belie its size and nearly two-and-a-half-ton curb weight.

What We Don't Like: The S8's interior gives a slight indication that the A8 is getting on in years, with subpar technology offerings compared with others in the supersedan class. The only way to get a USB port is to buy a $129 Audi Music Interface cable, for instance (although a proprietary adapter to connect to an iPhone is included), and the display screens use an older version of Audi's MMI infotainment software than do newer models such as the A4, Q7, and TT. Otherwise, it's hard to come up with many downsides to this all-encompassing sedan—even its fuel-economy ratings aren't bad for a car this quick, and its base price of $116,850 is significantly cheaper than the Mercedes-AMG S63 ($145,625) and the BMW Alpina B7 ($137,995).

Verdict: Simply incredible.

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