Three versions are available. The standard A8 boasts instant throttle response from its powerful 4.2-liter V8 and six-speed automatic transmission, while quattro all-wheel drive and an adaptable air suspension provide an excellent balance between handling and ride quality. The A8 offers a supreme sense of control with Gibraltar-like stability, benefits of its lightweight, Aluminum Space Frame that bonds the car into one cohesive unit.
The cabin is elegant and comfortable, and tops the class in finish quality. Audi's Multi-Media Interface, or MMI, integrates controls for various features and electronic systems into a big knob. It's a little easier to learn than BMW's iDrive, but it isn't easy. There is a learning curve and sometimes we find ourselves having to work harder to perform simple functions and wonder whether this is progress or burdensome technology.
The A8 L rides on a stretched wheelbase that provides more room and comfort for rear-seat passengers and uses the same engine as the A8.
The A8 L W12 upgrades to a 12-cylinder engine and a whopping 450 horsepower. It's the only 12-cylinder sedan from Germany's big three luxury brands with all-wheel drive.
The Audi S8 is powered by a 5.2-liter V10 and comes with a firmer suspension, faster steering, and bigger brakes. The S8 is distinguished by special trim and equipment inside and out. The S8 is perfect for triple digit speeds on wide-open highways and would be an excellent choice for a cross country race. It's also a good selection for getting away from enemy agents, for those in that line of work, particularly in bad weather. For driving through the neighborhood or in stop-and-go traffic, however, we found it suffers from an overly sensitive throttle that makes smooth takeoffs a bit too challenging.
For 2008, the A8 gets minor visual revisions and two new safety technologies: Audi Side Assist and Audi Lane Assist. Side assist warns of vehicles in the car's blind spots and Lane Assist alerts drivers when they have crossed lane lines without using a turn signal.
The Audi A8 retails at a lower price point than comparable Mercedes and BMW models, making it one of the better deals in its class.
Audi A8 4.2 ($70,690); A8 L 4.2 ($74,690); S8 5.2 ($93,300); A8 L W12 ($120,100)
A8 L models are five inches longer than the standard A8 and S8. (L stands for long-wheelbase.) Inside the car, those 5.1 inches translate entirely into increased rear-seat legroom. Choose the A8 over the A8 L if squeezing into tight parking spots is more important than a vast rear seating area, remembering that the standard A8's rear accommodations are quite expansive by typical sedan standards.
At 115.9 inches, the standard A8 is fractionally longer in wheelbase than a Cadillac DTS. The A8 L is essentially the same length overall as a Mercedes S-Class and BMW 750i. The A8 L wheelbase stretches 121.0 inches, which leaves it 3.6 inches short of the long-wheelbase Mercedes and 2.2 inches short of the long-wheelbase BMW. Other things being equal, a longer wheelbase offers more passenger room and increased stability at speed, but is less maneuverable on canyon roads and in tight parking lots. The Audi is an inch wider than the Mercedes-Benz and comparable to the BMW.
All the doors open extra wide, making it easy to get in and out. The flush, lever-style outside handles are attractive, but we find them harder to use than the type you can put your hand through, such as those on a Mercedes.
Standard on A8 4.2s are 10-spoke 18-inch alloy wheels with 255/45HR18 all-season tires; these provide excellent handling and ride comfort and superb grip in the wet. The optional 19- and 20-inch wheels and tires more aggressively fill the wheelwells and provide a surprisingly smooth ride in spite of their short sidewalls. The A8 L W12 gets the 19-inch wheel/tire package standard; with 20-inch wheels available and 18-inchers (which offer the best ride) offered as a no-cost option.
All models feature a tall, vertical grille that connects Audi's familiar horizontally split grilles over the front bumper, emphasized with a chrome surround.
The rear of the A8 models feature taillights that fit flush with the clean rear design. Turn signals use LED technology and feature side repeater lamps to signal your intentions to drivers alongside. Dual exhaust pokes from below the beautifully integrated rear bumper.
The S8 has a bolder front end, with a bright finish emphasizing the vertical elements of the family grille; and a honeycomb texture for the air intakes on either side of it. A red-and-black S8 badge is offset to the lower right. Sharp-eyed Audi-watchers might notice additional S8 badges on the front fenders and front brake calipers, as well as a V10 badge on each front fender and unique aluminum-look trim on the side mirrors and door handles. Subtle, too, are the S8's integrated deck-lid spoiler and light-reflecting panel in its rear apron; not so subtle are its four oval exhaust tips.
The aluminum space frame saves about 300 pounds compared to a conventional steel frame, allowing more features without overburdening the car with weight. An A8 L 4.2 weighs 150 pounds less than a BMW 750Li and only 23 pounds more than a Mercedes-Benz S550, neither of which have all-wheel drive. The A8 benefits from a highly rigid structure, which means less flex, and the A8 feels as if it's milled from a single block of bar-stock aluminum. A rigid structure is the key to a smooth ride quality and sharp handling.
The A8 seats are supportive and comfortable and adjust 16 ways. A memory feature keeps all the settings for four different drivers (or moods), including climate controls. Front and rear seats can be heated and ventilated. The center console provides generous storage, and the electroluminescent instrument panel adjusts brightness automatically according to ambient light. The four-spoke, leather-covered steering wheel with a hub fashioned to replicate the shape of the grille.
In the A8 L W12, virtually every surface that isn't carpeted is covered with leather, save the top of the dash and headliner, which is made of Alcantara. Order the Full Leather Upgrade and the dash gets covered in leather, too, as well as the whole of the inner door panels, instead of just an insert. The double stitching on the seats in contrasting colors is really wonderful.
The S8 gets special seats upholstered in two-tone Valcona leather with contrasting stitching; or in all black if that's what you prefer. The wood trim in the S8 is an almost-black Gray Vavona, which contrasts more sharply with the aluminum-look highlights. Carbon fiber trim is optional. The S8 comes with a three-spoke steering wheel wrapped in gray leather. Instruments are white-on-gray with italic figures.
A seven-inch color screen in the top-center of the dash of all models displays Audi's Multi-Media Interface, or MMI. Four buttons and a dial on the center console do the adjusting. This system is designed to consolidate interior functions into one control center, giving the driver lots of options without filling the dash with buttons. Audi's MMI features a shallower menu structure than BMW's iDrive, meaning you don't have to burrow as deeply through a maze of menus to get to the adjustment you want. Audi did not incorporate the climate controls into this system, and that's a good thing. Heating and air conditioning have traditional controls mounted high on the center stack, so you don't have to call up a menu to change the fan speed. You simply twist a dial. Occasionally, we twisted this when we really wanted to turn down the radio, but we learned. The MMI screen matches the look of the controls, and a Return button takes you back to where you were, like the Back button on a Web browser.
Virtually everyone we've spoken to, from auto reviewers to consumers, rates Audi's MMI better than BMW's iDrive. But some rate the Audi system only minutely better, and don't like it much at all. Most have found Jaguar's elegant and traditional controls to be the easiest of all. The point? Designing controls to manage the ever-increasing number of performance, entertainment and communications systems in luxury cars traveling at high speeds remains a young, inexact science. Audi's system takes some time to learn and, at times, we found the technology overwhelming and distracting.
Beyond finish quality, attention to detail is one of Audi's greatest assets. A secondary heater in the A8 is designed to heat up the rear cabin quickly. Ambient lighting in the interior allows control of mood in the cabin. Mood lighting is good. One small demerit is the power door that hides the MMI when the car is shut off closes i
The first impression at the wheel of an A8 is its smoothness. There's nothing remotely resembling a squeak or rattle, and almost no vibration in the cabin.
The 4.2-liter V8 delivers powerful acceleration, but its power delivery is sophisticated, not crude. The V8 responds with a muted roar to every poke at the gas pedal. No matter how fast the A8 4.2 is already going, the driver can tap into a deep well of acceleration-producing torque. Audi claims the 350-hp A8 4.2 can sprint from 0 to 60 mph in just 5.9 seconds. A sub-six-second 0-60 is quick. Top speed is electronically governed at 130 mph. In short, the A8 is fast traffic. The base engine is also the easiest on gas, with EPA fuel economy numbers of 16 mpg City and 23 mpg Highway. Those numbers aren't bad for a big, V8-powered luxury car, and they're bested only by the base engine in the Jaguar XJ.
The 6.0-liter W12, rated at 450 horsepower, is quite remarkable. The A8 L W12 is a blast to gas. Throttle response is immediate, and the 12-cylinder engine delivers acceleration-producing torque in a wide, flexible power band befitting a luxury carmaker's flagship sedan. The W12 pulls hard up to its 6200-rpm power peak, and it feels like there's still more power coming when it hits the rev limiter. Moreover, the revs translate to executive-class thrust. Audi reports a 0-60 mph time of 5.0 seconds, very quick, indeed, with top speed governed at 130. The W12 is remarkably refined, docile, and tractable, particularly given 450 horsepower, but it does have a hint of an overly sensitive throttle so you might have to recalibrate your foot to avoid lurching from a standstill.
The six-speed automatic that comes with either engine shifts up or down according to the driver's wishes, deftly sensing how quickly and how hard the throttle is mashed. The transmission features what Audi calls DSP (for Dynamic Shift Program), a form of smart software that selects from over 200 possible shifting programs to adjust to any individual's driving style. Upshifts are silky smooth in full automatic mode; in some instances, downshifts could come quicker, but the reserve of torque in either engine more than compensates for any shift lag. The automatic features Porsche's Tiptronic system, allowing the driver to slide it into a manually controlled mode and use either the shifter or available steering wheel paddles to choose gears. Manual shifting is never necessary, because the transmission is quite responsive in the automatic mode, but it can be fun. Here, however, we lodge a small complaint. Even in manual mode, the transmission will shift up at high rpm, rather than holding the selected gear, which seems to defeat the purpose of giving the driver manual control, but it's a good thing if you forget to shift. If you an even sportier shift program but don't want to select the gears yourself, you can put the gearshift in S. This mode holds gears longer and downshifts quicker to keep power more readily on tap. It also hurts fuel economy, so use it sparingly.
The quattro all-wheel-drive system of
The Audi A8 is fast, roomy, luxurious and exceptionally comfortable. It rides like a luxury car, yet it's taut and handles like a sports sedan. Loaded with innovation, the A8 is a thinking person's luxury car, more progressive, less traditional than a BMW or Mercedes. It's elegant but not arrogant, indulgent without being excessive. It's priced a little lower than comparable sedans from BMW and Mercedes-Benz, yet gives up almost nothing to either. V8, V10, or W12? In Germany, where the autobahn beckons with no speed limit, that would be an easier choice, assuming money is no object. In our land, the advantage of the W12 or the sporty S8 is more image than reality. The price premium for the W12 seems like a lot for image, but it is a wonderful 12-cylinder sedan with all-wheel drive and we think it's a good choice. The S8 is a mixed bag. Some will like its sportier moves, but others will be annoyed by the firmer ride and sometimes sensitive throttle.
NewCarTestDrive.com editors Mitch McCullough and J.P. Vettraino contributed to this report. Correspondent Kirk Bell contributed from Chicago.