Packing fewer cylinders but way better drivability, the Audi S8 is finally a serious contender.

Audi has been on a roll in recent years. The four-ring brand is inching ever closer to lineup-wide handling parity with BMW, upping its styling game with the A7 and is even on pace to surpass arch-rival Mercedes-Benz for the No. 2 spot on the global luxury sales chart this year.

For all of its successes, however, one chink in Audi's armor has been the S8. Despite packing a Lamborghini-derived V10, the last-generation model simply didn't have the juice to run with rival executive missiles, and it was never interested in playing when the road turned curvy, either.

Not content to concede the segment to its competitors, Audi has cranked up the power to a suitably prodigious level, developed a better-balanced air suspension and added even more luxury to create a new S8. All the ingredients are definitely present and accounted for, but can Audi deliver the goods?

We took to the curvy roads just outside of White Plains, New York during peak foliage season to find out.

A Better Sedan Through Technology

Like the A8 on which it's based, the new S8 uses an aluminum-intensive body and structure that helps keep weight to 44,00 lbs - that's hundreds less than everything else in the class save for the Jaguar XJ Supersport.

Central to the S8's identity is a refined new 4.0-liter V8 that boasts a deep well of torque down low in the rev range. With the help of two twin-scroll turbochargers nestled in the valley of the engine's V, the mill produces 520 horsepower and 481 lb-ft of torque from 1700-5500 rpm. Those figures represent sizable gains from 450 horsepower and 398 lb-ft of twist churned out by the old car's sonorous but peaky 5.2-liter V10.

The V8 teams with an eight-speed automatic transmission, and pair is good for 15 mpg in the city and 26 mpg on the highway - impressive stuff in comparison to the V10's 13/19 mpg ratings. Less displacement and fewer cylinders are partially responsible for the increased mileage, but the other element of the efficiency equation is a cylinder-deactivation system that effectively turns the engine into a V4 in low-throttle cruising situations.

Dubbed "Cylinder on Demand," the setup uses several tricks to eliminate NVH issues that would be unbecoming for a six-figure luxury sedan, including active noise cancellation technology and active engine mounts that cancel out uncouth motor shudders by transmitting opposite vibrations.

Also part of the S8's vast technological arsenal is Drive Select, a system that lets the driver tailor the throttle response, steering effort and shift calibration to his or her tastes. Drive select also controls the air suspension and its continuously variable dampers.

Audi's quattro all-wheel-drive system is of course standard; in this application, it serves up a 40:60 front/rear power split and works in conjunction with a rear torque vectoring system that can send power to the outside wheel to minimize understeer or oversteer.

Audi decided to keep the visual modifications relatively understated, adding a new grille with chrome bars, a sportier lower fascia, revised side sills and matte-aluminum mirror caps. Around back, a diffuser and quad oval exhaust pipes complete the look. The changes to the already posh and palatial interior are also small, but quite effective - carbon fiber trim adorns the dash (wood is an option), while 22-way adjustable front sport seats let nearly anyone find a comfortable position.

Insofar as the concept can apply to a vehicle that starts at $110,000, the S8 is actually a decent bargain - an Alpina B7 runs about $20,000 more, while the Mercedes-Benz S63 AMG carries a $30,000 higher MSRP.

Refined rocket ship

Audi states that the S8 can sprint from zero-to-60 mph in a scant 3.9 seconds, and based on our experience we have no reason to doubt that claim - in fact, it may even be conservative. Floor the throttle and the big sedan simply surges down the road - it threw us back into our seat, the autumnal scenery started to blur and other cars suddenly became increasingly small dots in the rearview mirror. It's a strange and wonderful thing that something this big and coddling can move so quickly.

The eight-speed automatic is a boon to the engine's accelerative efforts, serving up rapid and well-timed shifts. Though gearchanges can be summoned manually via sturdy-feeling paddle shifters, due to the quick-revving motor and multiplicity of gears we often found ourselves throwing the stubby shifter into sport mode and leaving the transmission to its own devices.

Toss the S8 into a turn, and the big sedan responds admirably but is never quite able to make you forget about its 4,400-lb. heft. The steering is communicative, accurate and confidence-inspiring, but even with Drive Select in dynamic mode, we noticed a fair amount of body movement in sharp curves and when maneuvering to avoid oblivious leaf peepers. On the upside, the suspension is firm but never harsh, even over the most maintenance-neglected roads.

Leftlane's bottom line

Polished, lightning-quick and surprisingly efficient, the S8 is strong in nearly all the areas where its predecessor fell short. It still isn't exactly a corner-carver - to be fair, few cars this size are - but it is a superb all-rounder and a strong value.

Those in the market for an impeccably-appointed, impossibly-fast large sedan would be well served to take a serious look at the S8.

2013 Audi S8 base price $110,895

Words and photos by Nat Shirley.