Under the bonnet, the new Audi S8 Plus features a more powerful iteration of the 4.0-litre direct-injection twin-turbo V8 that motivates the regular S8. Power is now rated at 445kW and torque climbs to 700Nm or 750Nm in overboost mode.
In order to extract an extra 63kW and 50Nm from the 4.0-litre V8, Audi and Quattro developed a new engine control module, modified the exhaust valves and optimised the internal geometry of the turbochargers.
According to Audi, the S8 Plus can complete the 0-100km/h dash in 3.8 seconds or 0.3 seconds faster than the 445kW S8. The S8 Plus can hit an electronically governed top speed of 250km/h, although in some markets the electronic leash is let out to 305km/h as standard.
As with the regular S8, the S8 Plus channels the V8's thunder to all four wheels via an eight-speed automatic transmission. The S8 Plus rides a retuned adaptive air suspension system, and 21-inch alloy wheels shod with 255/35 tyres at the front and 275/35 rubber at the back. Stopping power comes courtesy of carbonfibre-reinforced ceramic brakes.
Visually the S8 Plus is distinguished by a lip spoiler on the boot lid; glossy black single frame grille, wing mirrors and window surrounds; carbonfibre flaps on its air intakes and front apron; a revised rear diffuser; dark exhaust tips; and tinted tail-lights.
Standard features include matrix LED headlights, stainless steel pedals, leather seats with contrasting red stitching, Alcantara trim all over, interior ambient lighting and power-operated doors.
The S8 Plus starts entering Audi showrooms across the world from November 2015.