For some time Audi (and every other automaker producing performance machinery) has been chasing BMW and its iconic M3 sports sedan. Over the years the boys and girls from Ingolstadt have outfitted their S4 model with a bewildering array of engines (everything from a turbo V6 to an aspirated V8) in their effort to match the M3’s incredible level of performance. For 2011 Audi’s S4 comes closer than ever to eclipsing BMW’s best, courtesy of a supercharged V6 motor and some trick drivetrain bits. The S4 is a breathed-on version of Audi’s stalwart A4 sedan. A clean-sheet redesign last year added 8 inches to the platform’s wheelbase, making the S4 among the roomiest executive expresses on the market. Also new was the aforementioned blown V6, a 3.0-liter, direct-injection unit that uses a Roots-type supercharger to produce 333 hp and 325 lb/ft of torque. While these numbers are impressive, they fall short of the 414 hp produced by the M3’s 4.0-liter V8. The newly enlarged S4 also weighs in at two tons, about 300 pounds more than the svelte M3. Yet despite the power deficit and weight penalty, the latest S4 manages to out-BMW BMW, providing a superbly integrated, polished driving experience that flatters even the most ham-fisted pilot. Despite giving up a full liter of displacement (and nearly 100 hp) to the M3, the 2011 S4 storms to 60 mph in 4.9 seconds, just six-tenths slower than the Bimmer. Part of the credit for such ferocious acceleration belongs to the Audi’s Quattro all-wheel-drive (AWD) system. The Quattro hardware (and its now familiar TORSEN center differential) combines with sticky Dunlop SP Sport Maxx tires to launch the S4 out of the blocks in a manner reminiscent of an F/A-18 being catapulted off the deck of the Nimitz. Shifting duties are handled by either a traditional six-speed manual or a novel dual-clutch "S-tronic" transmission with seven cogs. The new stick finally matches the Swiss-watch precision of BMW gearboxes, while the robotized seven-speed unit swaps gears with astonishing speed. Of particular note is Audi’s new sport rear differential. This so-called "active" unit can vary torque side-to-side at the rear of the car, allowing the S4 to attack corners with boundless enthusiasm. The nifty rear end (an $1,100 option that should be considered mandatory) banishes any trace of understeer, always an issue in older, nose-heavy S4s. The S4’s four-wheel multilink suspension also benefits from optional Audi Drive Select adjustability, whereby the driver can vary damping rates and steering effort to suit his or her mood. Speaking of steering, the 2011 S4’s rack is among the best in its class, delivering plenty of feedback and perfect weighting. In the hands of a professional driver, the M3 will almost certainly edge out the S4. Its finely tuned rear-wheel-drive chassis has been honed by BMW’s wizardly engineers, and its punchy V8 engine positively snarls with power. While we’d all like to think of ourselves as Michael Schumacher, the truth is that anyone who doesn’t hold an SCCA National license will find it much easier to extract maximum performance from the S4. The combination of AWD and its whiz-bang chassis aids allow the S4 to grip the road with supernatural poise; it can make even the trickiest corners look easy. The 2011 S4 also handily outclasses the M3 as a daily driver. Its long-wheelbase chassis translates into generous rear legroom and a smooth highway ride, while the classy interior (long a staple of Audi products) impresses with tight panel gaps and slick Alcantara suede upholstery. Audi’s MMI stereo and navigation interface requires some familiarization, but it’s a cinch compared to BMW’s indecipherable iDrive. The comfortable seats are aggressively bolstered and feature myriad adjustments plus standard heating. Taking the boss to lunch? The S4 will convince your higher-up you’re ready for the corner office, while the highly strung M3 might suggest you’ll quit the moment a chance to star in "Fast and Furious 3" pops up. Audi offers two trim levels of the 2011 S4. The Premium Plus trim features high-intensity-discharge headlights, a 10-speaker stereo with SIRIUS satellite radio, and three-zone automatic climate control. The step-up Prestige trim sports 19-inch wheels (up from 18-inchers), along with GPS navigation and a megawatt Bang and Olufsen stereo. Both trims can be optioned up with the special rear end, the Drive Select adjustable suspension, and fragrant "silk" nappa leather. Standard safety features include front, front side, and curtain airbags plus electronic stability control, while rear side airbags and a blind-spot warning system are optional for both trim levels. Pricing has not been announced, but expect the 2011 S4 to start around $45,000. While not exactly affordable the S4 undercuts a comparably equipped M3 by nearly ten grand, all while providing similar performance and superior accommodations. The M3 may remain the hardcore driver’s sentimental favorite, but those of us who don’t spend their weekends at the track will find the S4 an impressively well-rounded machine.