Audi S8

The Audi S8 quattro is a high-performance version of the German luxury automaker Audi's flagship car, the full-size Audi A8. The S8 is produced at Audi's Neckarsulm 'aluminium plant', and it was introduced in September 1994. Like the A8, the S8 is only available as a four-door saloon/sedan, and both generations have been constructed from an all-aluminium monocoque, dubbed the "Audi Space Frame" (ASF), the S8 using the standard wheelbase platform, and is not available in the long-wheelbase of the A8L.
In September 1994, according to the official electronic parts catalogue for the Volkswagen Group, Audi introduced the Audi S8 4.2 quattro (Typ 4D) into the European market with a six-speed manual transmission, and a year later with tiptronic five-speed automatic transmission - a high-performance version of the Audi A8 in the vein of Mercedes-Benz AMG models, sharing the A8's all-aluminium monocoque "Audi Space Frame" (ASF), and Volkswagen Group D2 platform.
In the UK the S8 was only available with an automatic gearbox.

At the same time of the A8's facelift in late 1999, the S8 received the same cosmetic upgrades. This was the first model to be introduced to the North American market.

Production of this original S8 ended in September 2002, shortly before the introduction of the current D3-platform A8.

The D2 S8 was also featured in the 1998 film Ronin.
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 (parts code: 077, identification codes: AKH, AHC). 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 (identification codes: AQH, AVP, AYS, BCS). The AHC Code engine was the only 4 valve V8 and featured different exhaust cams, Different Ecu tune, and a higher compression compared to the ABZ(300)bhp engine of the A8. All S8 engines from 99-on had 5 valves per cylinder and compression bump to 11.0:1 from 10.8 giving the S8 355 BHP.
A sports-recalibrated version of the ZF 5HP24 five-speed tiptronic automatic transmission (parts code: 01L, identification codes: DYM, ECX) (gear ratios - 1st: 3.571, 2nd: 2.200, 3rd: 1.505, 4th: 1.000, 5th: 0.804), featuring "Dynamic Shift Programme" (DSP) was standard. European-market models also had a six-speed manual transmission option (parts code: 01E, identification code: DGV).

Torsen T-2 based quattro permanent four-wheel drive was also standard. Final drive ratio (for automatic transmission) is 3.730.
A retuned, 20 millimetres (0.8 in) lowered sports suspension included a 30% stiffer spring rate and 40% more compression damping in the shock absorbers. Speed-sensitive "servotronic" power assisted steering was also standard.

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). From 2002, an upgraded Bosch ESP 5.7 Electronic Stability Programme became standard fitment.

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. In 2003, 8Jx18" polished 9-spoke RS wheels became a no-cost option road wheel.