The most important changes are found by popping the hood. Starting with a stock S8-sourced twin-turbocharged 4.0-liter TFSI V8 engine, engineers have added tweaked turbos, a re-mapped ECU, and modified exhaust valves to squeeze 85 additional ponies out of the V8.
As a result, the plus boasts 605 horsepower and 516 foot-pounds of torque, though an overboost function can temporarily bump that figure up to 553 if additional power is needed. Bolted to an eight-speed automatic transmission, the eight-cylinder sends the behemoth from zero to 62 mph in 3.8 seconds – 0.3 seconds slower than a base-model R8 — and on to an electronically-limited top speed of 155 mph. With the limiter turned off, the S8 plus can hit the Autobahn at up to 189 mph.
The main visual differences between the plus and the stock S8 are black accents on the grille and around the windows, a gloss black air diffuser out back, black tail pipes, a trunk-mounted spoiler, and blacked-out tail lamps. The plus rolls on 21-inch alloy wheels, but it’s clearly aimed at buyers who wish to keep a low profile.
The discreet treatment continues inside, where the plus gains black leather upholstery with red piping and contrast stitching, piano black trim on the center console, and stainless steel pedals. The plus is only available with a regular wheelbase.
In Germany, the Audi S8 plus will go on sale this November with a base price of €145,200, a lofty sum that converts to approximately $158,000. It’s not too far-fetched to speculate the S8 plus will join Audi’s North American lineup as a 2016 model, but the Volkswagen-owned car maker has not commented on the matter.