Just like the outgoing A8, the new car uses the Audi Space Frame (ASF) structure. The assembly, co-developed with Alcoa, features aluminum panels over a rigid spaceframe of the same material. Audi claims the ASF saves 280 pounds versus a traditional steel unibody. Torsional rigidity is said to be 60 percent greater than that of the old A8, which helps the handling greatly. The main difference between the old and new A8s is the addition of a sophisticated air suspension that's shared with the VW Phaeton. This setup complements a four-link (control arm) front end and a multi-link rear. The air springs operate in four different settings, labeled Lift (for semi-off-road excursions up to 50 mph), Comfort, Automatic, and Dynamic. Seventeen-inch wheels with 235-series all-season tires are standard, but Audi offers both eighteen- and nineteen-inch rims as options, both sporting meaty 255-series performance tires.
On the road, Audi's new flagship is amazingly nimble, behaving more like a big-engined A6 than like an evolution of the previous A8. It is precise and responsive and remains entertaining all the way to the limit. If you enjoyed the old S8, you will particularly appreciate the new A8's Dynamic suspension mode; it lowers the ride height and tamps down the body in the twisties. If you want the optimal compromise between body control and ride comfort, put the suspension in Automatic and leave it there.
Even so, since the Audi set out to be a bit more dynamic than the Phaeton, the low-speed response to manhole covers and expansion joints is brittle. The new A8 is more chuckable and harder-edged than the old car but suffers from steering that needs more weight, too much initial turn-in understeer, and a tendency to run wide at the limit. On the credit side, the A8 has extremely energetic brakes and plenty of grip.
The A8 will offer one powertrain at launch in the States: a 40-valve 4.2-liter V-8 mated to a six-speed automatic transmission. The engine makes 330 horsepower, an increase of 20 over last year's unit, and 317 pound-feet of torque, up 15. The transmission has the familiar Tiptronic manu-matic setup, but we'd appreciate up- and downshift buttons on the steering wheel. Audi claims the A8 will accelerate from 0 to 62 mph in 6.3 seconds and will run to an electronically governed 155 mph.
The new A8 is a supremely competent, utterly complete premium luxury sedan. It sounds great, goes fast, and is terrifically entertaining when the pavement begins to curve. When the car arrives on American roads, it will almost certainly raise Audi's profile in this rarefied market segment. Moreover, the second-generation of the high-performance S8 is sure to widen the eyes of more than a few well-heeled shoppers when it arrives a year or so later.
Is the new A8 revolutionary or merely evolutionary? Audi is betting on somewhere in between. The company expects to sell some 7000 examples of the new A8 in North America, which sounds modest until you realize that at their peak, sales of the old A8 barely topped 3500.