The Audi S8 is a full-size luxury car of the Audi S models produced by the German automaker Audi AG, manufactured by Audi Sport GmbH at the Neckarsulm plant. The S8 is the mechanically-upgraded, high-performance version of the Audi A8, fitted standard with Audi's quattro all-wheel drive system, and was only offered with a short-wheelbase for the first three generations, being joined by a long-wheelbase variant option for the fourth generation.
(D2) First generation
Audi S8 (D2) was produced from 1996 to 2003. The car featured a 4.2 liter V8 with . The D2 S8 could accelerate from 0– in 6.2 seconds. It has a curb weight of . In 1999, the car was updated with a power increase to , which brought the 0– acceleration down to 5.6 seconds. Top speed was electronically limited to . It has a curb weight of . An Audi S8 (D2) was chosen as the car of the protagonists of the film Ronin.
(D3) Second generation
Audi S8 (D3) was released from 2006 to 2010. The car was equipped with a modified V10 engine shared with the Lamborghini Gallardo of the same years. It produces , detuned by from the Gallardo's power output of with the purpose of increasing its fuel efficiency. The top speed is electronically limited to . Acceleration from 0– takes 5.1 seconds. It has a curb weight of .
(D4) Third generation
Audi S8 (D4) (2012–2015, facelift 2015–2018) 3,993 V8 TFSI. It produces . It accelerates from 0- in 3.6 seconds, bests the quarter mile in 11.9 seconds at and reaches a top speed of . Curb weight is .
In 2016, the S8 plus version was launched with an increased engine power of . Acceleration from 0– takes 3.3 seconds and with the Dynamic Package it can reach a top speed of . Unlike the regular S8 which was built by Audi on the regular assembly line alongside other A8 variants, the S8 Plus was built by Audi Sport (formerly Quattro GmbH) and has a VIN that starts with WUA to identify it.
(D5) Fourth generation
The release of the fourth generation S8 was planned to begin in 2019–2020. For the first time, it was to be offered in both short and long-wheelbase versions, with the long-wheelbase S8 (i.e., an S8L) being the sole variant offered in North America. The S8 is now the flagship of the Audi A8 range, since the nominally higher-end A8 L W12 was no longer offered after the 2018 model year.
The Audi S8 (D5) features and of torque as a result of its 4.0-liter twin-turbo V8. A 48-volt mild hybrid system will allow for stop-start use and coasting. Compared to the S8 plus (D4), the S8 (D5) has less but more torque.