The Audi S8 quattro is a high-performance version of the German luxury automaker Audi's flagship car, the full-size Audi A8. Like the A8, the S8 is only available as a four-door sedan
The S8, like all Audi "S" models, is fitted as standard with Audi's trademark quattro four-wheel drive (4WD), with the S8 using the Torsen-based permanent 4WD system.
At the same time of the A8's facelift in late 1999, the S8 received the same cosmetic upgrades.
Motive power in the D2 S8 powertrain featured an uprated, 250 kilowatts (340 PS; 335 bhp) version of the standard 4 Valves per Cylinder 4,172 cubic centimetres (254.6 cu in) 90° V8(AKZ) petrol engine. From late 1999, the engine was given a further 5 valves & power increase to 265 kilowatts (360 PS; 355 bhp) at 7,000 rpm, and 430 newton metres (317 ft·lbf) of torque at 3,400 rpm.
The brakes featured Bosch ABS 5.3 Anti-lock Braking System, with Electronic Brakeforce Distribution (EBD), and worked radially ventilated front discs of 345 millimetres (13.58 in) in diameter by 30 mm (1.18 in) thick. The rear vented discs measured 280 mm (11.02 in) by 22 mm (0.87 in).
Standard alloy wheels were 8Jx18" cast aluminium alloy "Avus" 6-spoke style, with 245/45 ZR18 Dunlop SP Sport 8000 or Bridgestone Potenza RE040 performance tyres. From 1999 model year, an 8.5Jx20" polished "9-spoke RS" wheel became an option, shod with 255/35 ZR20 Michelin Pilot Sport tyres.
Whilst the S8 shared the aluminium monocoque of the A8, subtle detail included solid aluminium alloy door mirror housings, chrome-effect beltline and lower front grille trim, and polished twin exhaust pipes, along with subtle "S8" badging.
Source: Wikipedia, 2011