Optically, the high-tech brake system can be identified by the special cooling ducts and the perforation of the discs as well as by anthracite-coloured callipers with the "Audi ceramic" logo. A six-piston aluminium monobloc calliper is used at the front wheels, a nodular cast iron floating calliper at the rear. The dynamic stability system ESP is specially tuned for interaction with the ceramic brake system.



Body
Light and unshakable

As the sporty top model in the A8 line, the new Audi S8 makes use of the entire expertise that Audi has acquired in the body manufacturing sector. Since the debut of the previous generation in 1994, the Ingolstadt brand has made consistent progress in the field of aluminium construction.

It all stated with a revolutionary new approach - the Audi Space Frame ASF. This is a high-strength aluminium frame structure into which the large aluminium panels are integrated, thus assuming a supporting function. The space frame consists of a combination of aluminium extruded sections and castings that are positively connected to each other. Its central elements are the roof frame, side sills, seat cross members, roof posts and floor panels.

Innovative casting techniques and alloys are used for the current Audi A8 series. Multifunctional large castings, long continuous profiles and a high proportion of straight extruded sections reduce the number of parts used. Just 29 elements are used now instead of 50 castings, while the proportion of large castings has increased from 22 to 34 percent of structural weight compared with the predecessor. This progress improves comfort decisively because a lower number of connections between components makes it possible to increase body rigidity. At the same time, the fact that there are fewer components has a positive effect on production processes and, consequently, on quality. The side panel, for example, consists of a single section which extends from the A-post to the rear end of the body.

The connections are formed by riveting as well as various welding techniques including MIG and laser welding and, for the first time, the laser-hybrid welding process. Laser welding allows large-area panels to be connected to the body structure particularly efficiently thanks to the fact that the resulting linear joins achieve superior strength and rigidity values to punctual ones. The body of the new Audi S8 includes a total of 20 metres of laser connecting seams.

One of the two great strengths of the Audi Space Frame ASF is its outstanding rigidity. Its static torsional rigidity, a critical measure of dynamic potential, is around 60 percent higher than on the previous model. On the current Audi A8, the natural frequency of torsion - the primary determining factor behind vibrational comfort - has increased by 38 percent. The ASF meets all current passive safety standards as well as plenty that have not yet come into force. And thanks to its supreme engine power and highly rigid body, Audi S8 is permitted to tow a braked trailer weight of 2,300 kilograms.

Despite all these excellent qualities, the body structure weight of the Audi S8 is only about half as much as that of a conventional sheet-steel body. It weighs in at 215 kilograms - a figure otherwise usually to be found in the upper midsize class. This weight-saving has two advantages: it improves handling characteristics and reduces fuel consumption.



Design
Discreet sports style

The Audi S models have always epitomised high performance and refined sports appeal. The same applies to the S8 - it lends the design of the A8 a dynamic edge. This prestigious saloon is already inherently light and elegant in character - its aesthetic appeal reflects its exceptional position as a sports model in the luxury class. And because good design is always functional, the styling of Audi models always enhances drivability - there is extremely little lift at the rear axle, for example.

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