To say that the current 2015 Audi A8, which was launched in 2009, is a bit long in the tooth is an understatement. Sure, the German sedan->ke142 is still one of the most popular choices in the full-size->ke4304 market, but both Mercedes-Benz->ke187 and BMW->ke178 have redesigned their competitors for this demanding niche. The A8 desperately needs a modern interior and an exterior design that will attract new customers. Same goes for the performance-oriented 2015 Audi S8.

The A8's->ke1089 overhaul, however, won't happen until 2017, and this basically means an updated S8 won't arrive until 2018. The good news is that the next A8/S8 will borrow their styling from the gorgeous 2014 Audi Prologue Concept. Granted, the new design language is still evolutionary rather than revolutionary, but it's a breath of fresh air nonetheless. Meanwhile, Audi will probably continue to make the best of the current model with mild updates and special-edition models. The most recent of these is the S8 Plus, which, as the name suggests, is a more powerful version of the already familiar S8.

Audi's Plus line goes back to 2004, when the company sold a final, limited-edition version of the RS6.->ke1305 It had increased engine output, added standard features, and various other goodies inside and out. The same recipe was applied again in 2012 on both the 2014 Audi R8 V10 Plus and the 2012 Audi TT RS Plus, which makes the S8 the fourth Audi to receive this package and the first S model to get the "Plus" badge.

Updated 11/13/2015: Audi announced U.S. prices for the new S8 Plus which will be put on sale in December 2015. Prices will start from $114,900 - excluding $925 destination charges.

Continue reading to learn more about the 2016 Audi S8 Plus.

Exterior

Though the S8 isn't the kind of sedan I'd describe as beautiful, I admit its clean and almost featureless body lines give it an elegant stance a lot of modern, full-size sedans can't brag about. What I like more about the S8, especially compared to the 2014 Mercedes-AMG S63, is that it packs all the performance in a rather mundane shell, which basically turns it into a sleeper. The S8 Plus is pretty much the same, missing the overly aggressive body features that would alter its simple yet stylish design.

Simply put, aside from the spoiler lip on the trunk lid, there's absolutely no hint that the S8 Plus packs significantly more power than its S8 sibling. Come to think of it, a spoiler lip is not even a hint these days, when so many cars are designed to look faster and more powerful than they actually are.

Getting back to the car in question, the said spoiler lip is standard equipment and comes painted in the same color as the exterior. However, Audi does offer the option of a carbon-fiber piece for a more upscale look. Speaking of carbon, the entire exterior design of the S8 Plus revolves around a blacked-out appearance. The trademark Singleframe grille is finished in gloss black, while the honeycomb mesh of the side air inlets are in matte black. Both the flaps in the inlets and the splitter-like piece on the front apron are made from carbon fiber.

On the sides, the S8 Plus features black window trim and mirrors caps that can be optioned in either gloss black or carbon fiber. The standard housings are painted in body color. Around back, the sedan received tinted taillights, a gloss-black diffuser insert with a carbon-fiber surround, and gloss-black exhaust pipes. Other features include "S8" logos front and rear, "V8 T" badges on the front fenders, and Matrix LED headlamps. The latter, however, are standard only in Germany.

The S8 Plus also comes with an exclusive exterior color, Floret Silver, in addition to all the shades offered on the standard S8.

Interior

For the S8 Plus, Audi enhanced the S8's already sporty interior with a number of features otherwise only available as expensive options. The black full-leather interior comes with contrast stitching and piping in Arras Red, while the headliner is finished in black Alcantara. There's Black Piano trim on the center console, and aluminum and carbon-fiber inserts on the dashboard. The instrument cluster, on the other hand, is standard S8 business, with gray dials, white pointers, and an "S8" logo on the tach.

The extensive standard features list for the S8 Plus also includes ambient lighting, a convenience key with sensor-driven luggage compartment locking, the Alcantara package, power-assisted door closing, and a DVD/CD changer. German-spec models also get the assistance package with Audi pre sense plus, four-zone deluxe automatic air conditioning system, Bose surround sound system, and MMI navigation plus with MMI touch.

Drivetrain

Fortunately, the Plus in the S8 Plus is more than just extra features inside and out. Thanks to an updated 4.0-liter V-8 that uses a bespoke engine control unit with "speed and charge pressure boosting," modified exhaust valves and revised inner turbocharger geometry, the S8 Plus throws down 605 horsepower and 516 pound-feet of torque (in overboost mode, the engine produces 553 pound-feet).

That's an 85-horsepower and 35-pound-feet improvement over the S8, which makes the S8 Plus the most powerful full-size sedan Audi has built as of yet.

With the enhanced output also comes a quicker 0-to-62 mph sprint, now estimated at 3.8 seconds. This makes the S8 Plus a tenth-second quicker than the standard S8. Also, the sedan is faster than a wide array of sports cars and luxury grand tourers, including the 2014-2015 Aston Martin Vanquish, the previous-generation Audi R8, and the 2015 BMW M4, just to name a few.

Not surprisingly, the beefed-up V-8 mates to an eight-speed Tiptronic transmission and Audi's Quattro all-wheel-drive system. other updates include 21-inch wheels wrapped in grippier tires, adaptive suspension, a tuned exhaust system and a sports differential.

Drivetrain Specifications

Prices

German pricing starts from €145,200 (around $158,380). That's a €28,300 (about $30,865) premium over the standard S8 and €1,400 (around $1,527) over the A8 L W12.

On the U.S. market the new S8 Plus will be priced from $114,900 - excluding $925 destination charges.

Competition

2014 Mercedes-Benz S63 AMG 4Matic

Redesigned for the 2014 model year, the Mercedes-Benz S63 AMG is the S8 Plus' sole competitor in this niche. Significantly more aggressive on the outside and arguably the more modern choice as far as amenities go, the S63 AMG uses an updated 5.5-liter V-8 that cranks out 577 horsepower and 664 pound-feet of torque. Obviously less powerful than the S8 Plus, the Merc->ke187 has more than 100 extra pound-feet of torque, which makes it nearly as quick as the Audi.

The sedan needs 3.9 seconds to hit 62 mph from a standing start, making it a tenth-second slower than the S8 Plus, but tops out at 186 mph. The Audi is limited at just 155 mph. In Germany, the limousine fetches €152,022 before options. Unlike the S8 Plus, the S63 AMG is available in the U.S. from $143,250.

Find out more about the Mercedes-Benz S63 AMG here

2016 BMW 7 Series

BMW->ke178 overhauled the 7 Series->ke323 for the 2016 model year, but, unfortunately, the new model still doesn't feature a performance-oriented version. However, because the new sedan is significantly lighter than its forerunner and employs revised engines, as well as new technology and improved amenities, the 7 Series is likely better than the S8 in just about any department except output and off the line acceleration.

The most powerful 2016 7 Series to arrive in showrooms will be the 750i xDrive, powered by a twin-turbo 4.4-liter V-8 generating 445 horsepower and 480 pound-feet of torque. The oomph is enough to push the sedan from 0 to 60 mph in 4.3 seconds, making it a half-second slower than the S8 Plus. However, given the 750i has 150 horsepower less than the Audi, that figure is nothing to sneeze at. German prices for the new 750i xDrive start from €107,500, while in the U.S. you can have it for at least $97,400.

Read more about the BMW 7 Series here.

Conclusion

While I'm no fan of recent products coming from Ingolstadt, especially since the brand's styling department adopted the "same sausage, different lengths" strategy, I can see why the S8 Plus has everything it needs to become an iconic model in the A8 lineup. It's nearly as powerful as the new R8 V10 Plus and only a half-second slower from 0 to 62 mph, yet it's able to remain inconspicuous until the pedal hits the floor. It's basically what most businessmen want from a high-performance, full-size sedan nowadays.

Updated History

Updated 09/21/2015: We've added a series of new images we took at the 2015 Frankfurt Motor Show. Find the new images in the "Pictures" tab.

Updated 08/12/2015: Audi dropped two new video: one driving footage and one trailer - for its new S8 Plus. Check them out to hear the sound of the car's V-8 engine. Enjoy!