Audi S8 review
The Audi S8 is the performance flagship version of the classy, understated and hi-tech A8 executive saloon
Like all other Audi S and RS models, the S8 represents the fastest and most exclusive version available. Using the standard A8 saloon as its base, the S8 adds a twin-turbocharged V8 engine with more than 500bhp and aggressive styling tweaks to the exterior and interior. Unlike many of its rivals from Mercedes, BMW and Jaguar, the S8 features quattro four-wheel drive to help cope with the added power and as a result it also provides superb grip even in wet and wintry conditions. Despite the muscular performance, the S8 is still a quiet and comfortable limousine, with a luxurious and stylish cabin. However, while it is incredibly capable, the S8 is expensive and lacks the engaging dynamics of its rear-wheel-drive rivals.
Our choice: S8 4.0 V8TT quattro
The standard A8 has often been criticised for its bland styling but the S8 helps to address this problem by adding enormous 20-inch alloy wheels, a more aggressive single-frame chrome grille and a subtle body kit. At the back, a set of quad-exhaust pipes and special 'S' badging are the only clues to its performance potential. On the inside, the already high-class interior has been given a range of sporty upgrades, including grey-back dials, carbon-fibre trim and quilted leather and alcantara on the seats and dashboard. Standard equipment is very generous, too, with hi-tech kit like sat-nav, BOSE surround sound and climate control all fitted as standard. However even with these tweaks, the A8 fails to standout like the Jaguar XJ Supersports or even its smaller and cheaper sibling, the Audi S7 Sportback.
Although the Audi S8 uses the same 4.0-litre twin-turbo V8 as the lesser S6 and S7 models, the engine's power output has been increased to an incredible 513bhp and 650Nm of torque. This makes it blisteringly quick in a straight line, but thanks to the standard-fit quattro four-wheel-drive system and adjustable air suspension, it also offers up plenty of grip in the corners. That said, there's no escaping the fact that this a two-tonne car and at times it feels like too much weight for the brakes and steering to cope with. Plus, as the S8 comes with a very clever active noise cancellation system that makes it virtually silent at cruising speed, it means the S8 isn't as engaging as an AMG-badged Mercedes S-Class and its not as comfortable either.
While the S8 uses a new engine, the gearbox and four-wheel-drive system are both used in the standard car, while the interior is built to an incredibly high standard. There's a wide variety of complicated electronics on board, too, but Audi has a well-earned reputation for reliability that rivals like Jaguar can't really compete with. That said, despite this strong tradition the brand only returns average scores in the annual Driver Power survey and finished behind BMW and Mercedes in the overall standings in 2012. Safety should not be a concern in the S8, though, as its aluminium space frame chassis is very strong and technology, like two-stage traction control and a pre-sense system that prepares the car for a collision by tightening the seat belts and closing the windows, are included as standard. Options like a night-vision camera and radar-guided cruise control are also available.
The S8 offers the same generous level of space as the standard A8, which means a 510-litre boot. It also comes with an electric tailgate and an opening that's wide and flat, making it easy to load even the bulkiest of items. Rear seat passengers are well catered for, too, with enough head and legroom for three adults in the back and plenty of handy cubby holes. Up front, there's a huge range of adjustment for both driver and passenger and despite its dimensions, visibility is good so the S8 is fairly easy to park. It also features a massive 90-litre fuel tank to help improve its cruising range on the motorway.
Running a powerful and expensive car like the S8 will require very deep pockets. Although the new engine does use cylinder-deactivation technology to maximise efficiency, drive it hard and the S8 will struggle to return more than 25mpg, while C02 emissions of 235g/km put it in one of the top brackets for road tax. Other consumables like tyres and brakes will also need replacing more regularly than with the standard A8 and repairs at an Audi approved dealer will be very costly. Big luxury saloons also struggle to hold onto their value so despite its premium image, the S8 will drop considerably in value after only a few thousand miles.