The Audi S8 is equipped with a V10 engine that capitalises on the expertise of the super sports car Lamborghini Gallardo. The 10-cylinder power unit develops 450 bhp of power and 540 Nm of torque from a swept volume of 5.2 litres. The torque value is achieved at as low an engine speed as 3,500 rpm. As on the Le Mans winning R8, the most successful racing car in the world, FSI petrol direct injection assures superior power output in the Audi S8. This luxury saloon sprints from 0 to 100 km/h in 5.0 seconds, and is electronically governed at 250 km/h.
The driveline and chassis of the S8 have been modified to reflect the engine's power. A quattro drivetrain of the latest generation with asymmetric/dynamic torque distribution diverts the engine's power to all four wheels. The firmer settings of the adaptive air suspension sport and modifications to the steering ensure that the power and dynamism of the drivetrain are translated with precision into locomotion.
In outfitting the S8 with the V10, Audi is introducing an engine technology that has long been demonstrating its performance potential in the world of Formula 1 racing. The Italian super sports car brand Lamborghini, a subsidiary of Audi, likewise regards the ten-cylinder engine as synonymous with dynamic power. This engine concept has a much more sporty emphasis than a comparable twelve-cylinder power unit. Ten-cylinder engines are more compact and lighter; thanks to the smaller number of components, they have lower moving masses and less internal friction.
The 450 bhp V10 is the second generation of Audi V-engines, all with a 90-degree included angle and a spacing of 90 millimetres between cylinder centres. Key areas of the Audi version have been reengineered compared with the engine in the Lamborghini Gallardo. The bore has been increased from 82.5 to 84.5 mm; the stroke is 92.8 mm and the displacement 5204 cm3. A so-called bedplate structure – an intermediate frame – reinforces the extremely compact crankcase, which is made from cast aluminium.
The powerful ten-cylinder engine is designed for impressive torque as well as engine power. It generates 450 bhp at 7,000 rpm, but musters up 540 Nm of torque at just 3,500 rpm. 90 percent of the torque is available from as low as 2,300 rpm. The V10 exhibits spontaneous throttle response and very refined running, and under load it also produces sonorous acoustics, as befits a dynamic car.
The V10 imparts the luxury saloon with the road performance of a high-calibre sports car. The Audi S8 races from 0 to 100 km/h in 5.0 seconds. The speed is not governed electronically until the needle reaches 250 km/h. The engine shows a distinctly modest thirst, needing only 13.9 litres of fuel per 100 kilometres – a figure achieved partly thanks to the consistent use of lightweight design, which clearly sets the A8 range apart from its competitors. With its innovative aluminium body, the Audi Space Frame ASF, the S8 weighs just 1940 kilograms, including the dynamic, sure-footed quattro drive. On the new Audi S8, every horsepower has to propel just 4.31 kilograms – the power-to-weight ratio of a sports car.
The innovative lighting technology adaptive light with LED daytime running lights is standard equipment on every Audi S8. Here, the xenon plus headlights are equipped with static turning lights and dynamic cornering lights. The separate LED daytime running lights, each of which consists of five white light-emitting diodes and consumes only a minimal amount of energy, can be considered a pioneering invention.
Source: Audi press