America’s enduring devotion to the V8 engine may falter this week when the wraps come off the potent new V10 FSI-powered Audi S6 quattro at the North American International Auto Show in Detroit (January 8-10). Developed with technical input from Lamborghini, the quattro four-wheel-driven, 420PS ten-cylinder Audi super saloon will be available to order in the UK from April and will reach its first UK customers in July. Avant estate versions combining exceptional performance with up to 1,660 litres of carrying capacity will be launched simultaneously.

Using the Gallardo super car’s 5.0-litre unit, developed by Lamborghini in conjunction with Audi, as its foundation, the new 5.2-litre V10 FSI engine that appeared first in the new S8 quattro has been tuned to suit the specific characteristics of the new A6 range flagship. Its adjusted output of 420PS is delivered at 6,800rpm, and peak torque of 540Nm is on tap between 3,000 and 4,000rpm, with over 500Nm available from just 2,500rpm right up to 5,500rpm.

Channelled through a six-speed tiptronic automatic transmission with software revisions that enable even swifter gear changes than existing A6 models, this exceptional output gives the new S6 quattro the potential to cover the 0-62mph sprint in 5.2 seconds (Avant 5.3 seconds) and to reach a top speed limited electronically to 155mph. It can also cover a respectable 21.0mpg on the combined cycle.

In the pursuit of performance that is more commonly associated with exotic sports coupes, the fact that the S6 quattro is first and foremost an A6 was never forgotten. Bespoke features including Audi FSI direct petrol injection and a balancing shaft ensure that although the engine note and breathtaking response befit a super car, efficiency, smoothness and refinement remain typically Audi.

Weighing in at a comparatively light 220kg, the new engine also has a surprisingly modest impact on the 1,910kg overall weight of the S6 quattro, contributing to an impressive power-to-weight ratio of 220PS per ton for the Saloon.

The first ever V10 from Audi is effectively harnessed by sports suspension incorporating a high proportion of lightweight aluminium for maximum agility, and unique settings that strike the best possible balance between ride comfort and handling poise. The reassurance of smooth, unruffled acceleration and outstanding grip in all conditions comes courtesy of the latest generation quattro permanent four-wheel-drive system, featuring a standard torque split of 40:60 (front / rear) that helps to optimise balance, adjustability and steering precision.

In common with generations of sporting Audi models, the new S6 quattros don’t flaunt their capabilities to the outside world. Subtle hints include a unique front end design incorporating a restyled single frame grille and an additional central air intake flanked by larger side intakes containing distinctive LED daytime running strip lights. Front wheel arches flared by 14mm, aluminium look door mirrors and larger body-coloured side rubbing strips enhance the profile in conjunction with 19-inch 5-arm Wing design alloy wheels. At the rear, an integrated boot or tailgate spoiler, a built-in diffuser in a contrasting colour and four ellipsoidal exhaust tailpipes subtly complete the look.

Inside, new Alcantara and leather-upholstered sports seats with integral head restraints and pronounced lateral supports are a focal point, as is the ‘S quattro’ three-spoke leather-trimmed sports steering wheel with contrasting double seam stitching and aluminium look tiptronic gear shift paddles.

The sporting theme is continued in the facia and doors, which are inlaid with carbon fibre, and in the instrument panel, which features a new ‘Flexmetallic’ anthracite-coloured metallic covering and incorporates exclusive dials embossed with the S6 logo. Also new within the instrument panel is an upgraded Driver’s Information System (DIS) with a built-in digital speedometer.

Full UK specification and pricing for the new S6 quattro Saloon and Avant models will be announced nearer to their April on sale date.