At first glance, the Audi A8 has crisp, uncluttered lines with aggressively swept back headlights and roofline. Filling the wheelwells is a choice of wheel designs and sizes ranging from sedate to sporty. All in all, this is an understated, handsome sedan that doesn’t shout, "I’ve got money," yet still exudes class.
Inside the Audi A8, a spacious and beautifully finished interior greets the driver and passengers. Audi has a strong reputation for having what many consider the best cabins in the business, and the A8 maintains that lofty standard. Regardless of cost, there’s nary a car that could top the top-shelf materials and design flair of the A8’s inner sanctum. Audi’s Multi-Media Interface (MMI) handles everything from the navigation and audio systems to the adjustment of the driver-selectable air suspension. MMI features a 7-inch monitor that automatically glides (and hides) into the dash when not in use. Mounted in the console and operated via a simple twist-and-press knob and four large buttons that surround the knob, Audi’s MMI may draw comparisons to BMW’s iDrive system. But unlike iDrive, MMI is simple and intuitive to operate.
Under the hood if this Audi car you’ll find one of two engines. For starters, there’s a refined 4.2-liter, 40-valve V8 that makes a scintillating 335 horsepower and 317 pound-feet of torque. If that’s not enough, consider the 6.0-liter W12 power plant, which provides 450 hp, 428 lb-ft of torque and a 5.8-second 0-to-60-mph time. In either case, a six-speed Tiptronic automatic transmission sends the power to all four wheels through Audi’s quattro all-wheel-drive system. Under the A8’s aluminum skin, Audi employs an aluminum alloy space frame that is stronger and lighter than a comparable steel structure. This architecture has 20-percent fewer parts than the previous-generation Audi A8, yet boasts considerably greater (60 percent) torsional rigidity.
Audi’s engineers are especially proud of the A8’s air suspension, claiming it provides the handling of a sports car with the ride of a luxury sedan, and based on our experience, they’re not too far off. The adaptive air suspension adjusts itself to road and driving conditions, automatically firming up when the car is pressed through the curves and softening when cruising down the interstate. The driver can select one of four settings for the adaptive system: dynamic (lowest ride height and firm damping), automatic, comfort and lift (raises the car up for travel on rough roads). With its polished demeanor, spacious and luxurious cabin and capable road manners, the 2006 Audi A8 leaves little to be desired. And at a price tag thousands less than its chief rivals, we would strongly suggest visiting the dealer of the four rings before putting down your big money.
Powertrains and Performance
Standard A8 and A8 L models come with a 4.2-liter, 40-valve V8 that generates 335 horsepower and 317 pound-feet of torque. Named after the engine that makes it special, the W12 model has a 12-cylinder engine that make 450 hp and 428 lb-ft of torque. The engine consists of two narrow-angle, 15-degree V6 engines joined at the crankshaft, a more compact design than a conventional V12. Both engines are matched to a six-speed Tiptronic automatic transmission that drives all four wheels through Audi’s quattro all-wheel-drive system.
Peace-of-mind features include stability control, 10 airbags (including four side, front knee and full-length head curtain) and a first aid kit in the rear center armrest.
Interior Design and Special Features
Whether you sit in the pilot’s seat or stretch out (and with 42 inches of rear legroom in the L, we mean stretch out) in back, everything you see and touch in the 2006 Audi A8 bespeaks the highest quality. Generous fillets of dark or light wood, suede trim and aluminum accents are arranged attractively. With 16-way power adjustment (including upper seatback angle for the shoulders) and a power tilt/telescoping steering wheel, finding a comfortable driving position is easy for short and tall folk alike.
Throttle response is gratifying with either engine. Whether taking off from a stoplight or jetting up to cruising speed on the freeway, a solid rush of power is always on tap. The main difference is that the Audi W12 simply has more power on reserve. Powerfully reassuring brakes that are easily modulated have no problem reining in the Audi A8. The air suspension is well sorted; left in automatic mode the system works just fine providing a soft but not mushy ride and solid composure through the twisty bits. And when used in the dynamic setting, body lean is kept to an absolute minimum, making the A8 feel more like a compact sedan rather than a large flagship sedan.
Impressive handling characteristics, pioneering technology and highly exclusive design and equipment – the Audi A8 redefines sports appeal in the luxury segment in a unique and masterly fashion. As the flagship of the brand it incorporates all the progressiveness present at Audi.
Measuring 5.06 metres in length, the Audi A8 is the sportiest saloon in the luxury segment, yet lacks nothing in terms of elegance. The long-wheelbase version, with a wheelbase extended by 13 cm to 3.07 m, embodies the ideal of a luxurious saloon for long-distance driving. The long-wheelbase versions are available for all engine variants.
From its outward appearance alone the A8 is clearly a sleek, sporty luxury-class saloon. The design is an expression of its unique character. Expansive, arching surfaces are framed by precise lines. The flat front end, the imposing wheels, the low, long sweep of the roof and short overhangs visualise the notion of ease upon which the entire vehicle is based. The drag coefficient of the A8 – a technical field in which Audi has played a leading role for many years – is only 0.27. Developments such as the faired underbody allow substantial downforce on the axles. Turbulence has been reduced thanks to intensive fine-tuning, which also improved the aeroacoustics: even at high speeds, it is pleasantly quiet inside the A8.
The body of the A8 is based on the continuously enhanced ASF (Audi Space Frame) aluminium construction principle. This is a high-strength aluminium frame structure into which the large aluminium panels are integrated, thus assuming a supporting function. It weighs a mere 215 kilograms – putting it at the forefront of the luxury class. The Audi A8 3.2 FSI consequently weighs only 1,690 kg.
The reduced number of body components for the Audi Space Frame has improved static torsional rigidity, a decisive measure of vibrational comfort and dynamic handling potential, by 60 percent. The Audi Space Frame is a high-tech body structure, the building of which sees the interplay of new alloys, innovative casting techniques and newly developed joining methods, including laser-hybrid welding, a particularly efficient process for enhancing body rigidity.
The high-strength structure of the A8 exhibits excellent safety characteristics. In the event of a side-on collision, for example, the high-strength A-post braces itself against the other vehicle – it is a large multifunctional casting that effectively demonstrates Audi’s unrivalled expertise in the field of aluminium technology. Inside, the restraint systems, including active head restraints on the front seats, are precisely matched and work together.
In the luxuriously designed and impeccably finished interior the driver will find an operating concept that caused a sensation when the model line was launched at the end of 2002: MMI, the multi-media interface. Its concept, featuring a large colour display and central controller surrounded by four menu buttons, made an immediate impression and today sets standards with regard to operating convenience and user-friendliness.
The most important operating functions can be controlled from the steering wheel or via the optionally available speech control system; a five-inch central display in the cockpit recently replaced the previous smaller display. All switches and levers in the Audi A8 are clearly arranged; the electromechanical parking brake significantly enhances comfort and convenience in city traffic. The seats – electrically adjustable at the front – provide perfect support for the body. There is ample space for all occupants.
Here is an engine beyond compare: the twelve-cylinder power unit in the form of a double "V", or "W", for the Audi A8 6.0 quattro is quite unparalleled by any other modern-day unit. The "W" design principle has one inestimable advantage: despite the larger number of cylinder units, and despite a clearly higher displacement, the W12 is as compact as a V8 and thus has much smaller dimensions than a conventional V12 engine.
Three state-of-the-art petrol engines with aluminium blocks and two mighty TDI units make up the range of power plants for the Audi A8. The entry-level spark-ignition engine is the 3.2 FSI with six cylinders and a power output of 191 kW (260 bhp); thanks to the low weight of the A8 it manages on 9.9 litres of Premium fuel per 100 km. The new 4.2 FSI also comes with direct injection developed by Audi – the V8 unleashes 257 kW (350 bhp), 11 kW (15 bhp) more than its predecessor.
The top-of-the-range model is powered by a six-litre W12 of the utmost supremacy – it pumps out 331 kW (450 bhp) and develops a highly melodious, multifaceted acoustic profile. The sporty top model, the Audi S8, is propelled by a 5.2 l V10 FSI engine. Its power output of 331 kW (450 bhp) and its throaty sound ensure it lives up to this title.
The two diesels fascinate in a different way – with immense propulsive power and high performance coupled with fuel efficiency. They operate with common rail injection systems incorporating extremely fast-acting piezo injectors – a guarantee of superior refinement. Particulate filters are fitted as standard. The 3.0 TDI is a V6 delivering 171 kW (233 bhp); it uses just 8.4 litres of diesel per 100 km.
The latest generation of the twelve-cylinder engine has been substantially uprated. Its extra 30 bhp compared with the previous model in the first-generation Audi A8 represent an increase of seven percent in its power output. It can call upon 560 Newton-metres of torque across a broad speed range from 2,300 to 5,300 rpm. This gain – along with the 20 Nm increase in peak torque to 580 Nm – is the outcome of painstaking improvements to many different areas.
Another outcome of the engine’s enhanced efficiency is its fuel consumption of just 14.7 litres of Super Plus petrol per 100 km (overall value).
Inimitable twelve-cylinder sound
There’s no doubt that a successful twelve-cylinder engine owes a great deal to its highly typical sound. This means an extremely low-vibration idle-speed quality that is also free from low-frequency components. Audi’s acoustics engineers have in addition composed an extremely sporty, powerful sound pattern, albeit with a touch of refinement, for when this engine is accelerating at full load.
This unmistakable sound design combines the emotional and dynamic component with call for maximum acoustic quality, which ultimately also determines the overall character of the 12-cylinder A8.
4.2 TDI quattro
240 kW (326 bhp): with this extremely impressive power output, the new Audi A8 4.2 TDI quattro puts itself ahead of all the other diesel-engined cars on the international market. The entirely redeveloped 4.2-litre, eight-cylinder biturbo engine accelerates the lightweight saloon with its aluminium body from 0 to 100 km/h in just 5.9 seconds. The top speed is electronically governed to 250 km/h. In addition to these dynamic qualities, the new power plant displays the kind of refinement that sets standards even in the top segment of the motoring world, and ennobles the A8 4.2 TDI quattro, turning it into the perfect long-distance touring saloon.
The new engine is also exemplary in terms of economy. Combined as standard with quattro permanent four-wheel drive and 6-speed tiptronic transmission, it uses on average just 9.4 litres of diesel fuel for every 100 kilometres. This means it will cover more than 950 kilometres on a full tank without a stop. The Audi A8 4.2 TDI quattro is equipped as standard with a diesel particulate filter, which works without additives and consequently lasts the lifetime of the vehicle without servicing.
Biturbo with two intercoolers
A concept that has already proven its worth on the 4.0 TDI engine: two turbochargers with variable turbine geometry develop high torque even at low engine speeds, in conjunction with a high power output. Variable turbine geometry means that the flow of exhaust gas to the turbine rotor can be optimised depending on load and engine speed. By means of air mass metering, the engine management ensures that both turbochargers run constantly at the same speed and therefore achieve the same delivery rate. Maximum boost pressure is 2.5 bar; the turbochargers rotate at up to 226,000 revolutions per minute.
The variable turbine geometry is supported by electrically operated actuators on the new 4.2 TDI. These actuators adjust the vanes faster and with greater exactitude. Particularly at low engine speeds, this builds up the boost pressure faster and thus achieves an excellent response.
The 4.2 TDI engine is currently the most powerful diesel engine to be found in any production saloon car. 240 kW (326 bhp) at 3,750 rpm are the new benchmark – an increase of no less than 51 bhp over its 275 bhp predecessor.
Audi is introducing its pioneering petrol direct injection technology in the luxury class. The new Audi A8 3.2 FSI is powered by a six-cylinder engine developing 260 bhp, which combines free-revving high performance, refinement and economy all in one. With 40 bhp more power than its 3.0 predecessor, the 3.2 FSI is an engine befitting the sportiest luxury saloon in the premium segment, and a highly attractive entry-level engine for the Audi flagship model.
The Audi A8 3.2 FSI will be available both with front-wheel drive and quattro permanent four-wheel drive. The power generated by the front-wheel-drive six-cylinder model is handled by the continuously variable multitronic transmission. The A8 3.2 FSI quattro comes with a 6-speed tiptronic gearbox.
Two alternatives are also available in terms of vehicle dimensions. The A8 3.2 FSI can be ordered either with the standard wheelbase of 2,944 millimetres or in the long-wheelbase version, which has a wheelbase of 3,074 mm, an increase of 130 mm. This extra length provides additional space, entirely for the benefit of the rear passengers.
Just like its more powerful counterparts and the 3.0 TDI, the new Audi A8 3.2 FSI sports the exclusive front end with single-frame radiator grille, which was previously the distinguishing feature of the 12-cylinder A8.