Audi S6 and S6 Avant

Refined power in the sports luxury class

A refined flow of power in conjunction with superlative comfort and an elegantly understated appearance: this is the new Audi S6 / S6 Avant. It is the sporty top model in the luxury-class family of models comprising the Audi A6 saloon and A6 Avant, which took the market by storm following their launch in 2004 and have since garnered countless accolades worldwide from both customers and experts within the trade.

The S6, the latest product to result from the systematic application of Audi's philosophy of sportiness, will go on sale in the spring of 2006. Its appearance will coincide with the launch of the S6 Avant, the estate-car version that combines the exemplary versatility and variability of an Avant with the decidedly sporty character of the new Audi S6.

In response to the challenge to deliver supreme performance that always remains perfectly under control, the new Audi S6 will be powered by a completely new ten-cylinder V-configuration engine. This engine, a virtually identical version of which is likewise fitted in the new Audi S8, makes maximum use of its resources: with a displacement of 5.2 litres, it mobilises an output of 420 bhp (309 kW) at 6,800 rpm. It reaches its peak torque of 540 Nm between 3,000 and 4,000 rpm. Between 2,500 and 5,500 rpm, torque of over 500 Nm is available. This engine, weighing only 220 kilograms, is thus able to guarantee superior pulling power in every driving situation.

FSI petrol direct injection, a principle that has proved its worth in the most successful racing car ever built, the Le Mans winning Audi R8, plays an instrumental role in this model's refined flow of power. The saloon is capable of racing from 0 to 100 km/h in 5.2 seconds (S6 Avant: 5.3 seconds); the top speed is electronically governed to 250 km/h.

Both the driveline and the steering and suspension have been modified to reflect the immense power potential of the new Audi S6. The six-speed tiptronic automatic transmission, supplied as standard, accomplishes swifter gear changes; the steel-spring suspension is configured for greater agility and a more direct response, as is the servotronic steering. The latest-generation quattro permanent four-wheel drive with a 40:60 torque split naturally ensures optimum propulsion in all conditions. Thanks to this concept, the new Audi S6 sets itself apart as the progressive alternative to all its competitors.

One of the key requirements in the development of the Audi S6 was to provide a high standard of comfort in every situation, for all its sporty emphasis. This vehicle consequently also demonstrates over long distances that there is no inherent contradiction between refined power and the scope for the driver and passengers to enjoy a highly relaxing form of travel.

The interior offers a luxurious atmosphere. It features, for instance, new sports seats complete with integral head restraints, exclusive leather/Alcantara upholstery on all five seats and deluxe automatic air conditioning plus, with separate temperature distribution for the driver's and front passenger's sides.

For all the uncompromising and methodical nature of the technical concept, the external appearance of the Audi S6 is decidedly understated and elegant. The S6 saloon is characterised by such features as 19-inch wheels, subtly flared front wheel arches, the striking single-frame grille with vertical double struts and a harmoniously integrated rear spoiler, and the Avant has a modified roof spoiler.

The two daytime running light strips, each comprising five LEDs, are both a trendsetting safety element and an innovative masterstroke of design; they are integrated into the front bumper and, when switched on, serve as an unmistakable distinguishing feature of the S6.

Engine

Newly developed V10 with FSI technology and ample torque characteristic

Ten-cylinder petrol engines have long been regarded as a particularly sporty type of power unit. In the form of a V-engine they are short, compact and correspondingly light. The number of moving parts required for ten cylinders is moreover relatively low, bringing the added bonus of low friction losses. It is no coincidence that the Gallardo super sports car built by Lamborghini - an Audi subsidiary - is driven by a widely acclaimed V10 engine. The V10 in the new Audi S6 is a completely new engine which first appeared in the Audi S8 and has now been specifically retuned for use in the top model of Audi's luxury class.

Its ten cylinders are divided into two cylinder banks arranged at an angle of 90 degrees to each other, and each with two overhead camshafts (DOHC principle); the spacing between cylinder centres is 90 millimetres - one of the reasons why this 220-kilogram, four-valve engine is so compact. A special intermediate frame reinforces the cast aluminium crankcase.

The bore is 84.5 millimetres and the stroke 92.8 millimetres, producing a swept volume of 5,204 cc. With its crankpin offset of 18 degrees, the V10 fires at an ideal spacing of 72 degrees crankshaft angle. A balancing shaft located between the cylinder banks eliminates the free inertial forces of the first degree and contributes equally towards the engine's notable refinement.

All four camshafts are adjusted continuously through 40 degrees crankshaft angle depending on load and engine speed, thus optimising filling of the combustion chambers and consequently enhancing the power output. The camshafts are driven by no-maintenance chains and actuate the total of 40 valves via roller cam followers. The task of engine management is handled by two separate control units.

The V10 in the new Audi S6 uses FSI petrol direct injection. This permits a high compression ratio of up to 12.5:1 and therefore a highly efficient combustion process. The injection system delivers the fuel directly into the combustion chambers in precisely metered amounts, at a pressure of up to 100 bar.

The two-stage magnesium variable intake manifold incorporates electronically controlled tumble flaps; these induce a swirling movement in the air drawn in.

Innovative FSI technology has impressively demonstrated its potential in motor sport - the R8 racing car equipped with it participated five times in the Le Mans 24 Hours for Audi, winning the race on four of those occasions.

The powerful ten-cylinder engine is designed not simply with power in mind, but to an even greater extent for impressive torque. It achieves 420 bhp at 6,800 rpm, but delivers the peak torque of 540 Nm at engine speeds ranging from 3,000 to 4,000 rpm. Over 500 Nm of torque is on tap between 2,500 and 5,500 rpm. The engine exhibits spontaneous throttle response and very refined running, and under load it also produces sonorous acoustics, as befits this dynamic car.

The engine gives the Audi S6 the road performance of a high-calibre Gran Turismo. The Audi S6 saloon is capable of racing from 0 to 100 km/h in 5.2 seconds, and the S6 Avant takes a mere one-tenth of a second longer. The speed is not governed electronically until the needle reaches 250 km/h.

The engine consumes an average of approx. 13.4 litres of fuel per 100 kilometres.

The S6 weighs 1,910 kilograms (S6 Avant: 1,970 kg), including the dynamic, sure-footed quattro permanent four-wheel drive. Every horsepower consequently has to propel just 4.55 kilograms (S6 Avant: 4.69 kg) - the power-to-weight ratio of a top-notch sports car.

Drivetrain

More direct for even greater dynamism

The entire drivetrain of the Audi S6 has been designed from scratch. The engine's power on the S6 is translated into locomotion by a six-speed tiptronic as standard, which adapts to the driver's style by means of an intelligent feature. The software program that controls this automatic transmission electronically has been optimised to deliver more dynamic gear changes compared with other Audi models; the gear changes are noticeably swifter.

The driver can call up the transmission's "S" sport mode via the selector lever - it still performs upshifts even at relatively high engine speeds. And it is possible to change gear manually in both modes by means of the aluminium-look shift paddles mounted to the steering wheel. The selector lever has an aluminium look and - like the steering wheel - is trimmed in smooth leather.

The servotronic steering with its variable ratio has a more direct response than in the A6. This, too, results in even more agile handling.

Power and control

Typically for an Audi, the new Audi S6 likewise takes quattro permanent four-wheel drive as its basis. Its virtues are already widely acknowledged: superior traction in all driving conditions. More than a quarter of a century of expertise acquired in this domain by the Ingolstadt-based brand has led to the development of a new quattro generation with asymmetric/dynamic torque split - further evidence of Audi's guiding principle of "Vorsprung durch Technik".

A centre differential, installed longitudinally in the driveline, distributes power between the front and rear wheels, always according to the prevailing situation. The split in the basic setting is 40 percent to the front wheels and 60 percent to the rear. This slightly rear-biased torque split has been chosen to place even greater emphasis on the sporty, dynamic character of the Audi S6.

If the surface conditions change - for instance if they are wet or slippery, or if the car is driven onto a different type of road surface - the purely mechanical differential responds without any delay; depending on the road situation at any given moment, it can divert up to 85 percent of power to the rear wheels or as much as 65 percent to the front wheels. If a wheel on one axle spins (wheel slip), it is moreover brought under control by the Electronic Differential Lock EDL, which applies the brakes.

The electronic stabilisation program (ESP) shuts down in two stages: when the ESP button is pressed once, only the ASR traction control system is deactivated; ESP remains active, to stabilise the car if needed. The instrument cluster briefly displays "ASR off" and the ESP symbol remains permanently lit. This mode stays active in the S6 until ASR is switched back on by pressing the ESP button a further time. On the S6, ASR does not cut in automatically once a defined speed is exceeded (as is the case on the A6 / A6 Avant). If the ESP button is pressed for longer than three seconds, all ESP functions are switched off. Only the electronic differential lock EDL and ABS remain active. Pressing the ESP button a further time switches all ESP functions on again. As a result, the desired degree of electronic assistance can be determined by the driver via the ESP button. Without ASR traction control, the degree of stability can, within certain limits, be determined by the driver via the accelerator pedal. This permits a decidedly sporty driving style if desired.

The drivetrain concept of the new S6 always ensures that the enormous forces generated by the V10 engine can genuinely provide efficient, minimal-loss propulsion, something that vehicles with one driven axle only rarely achieve. It is consequently able to develop and use high levels of power all the time.

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