Audi's Adrenal RS 4

Audi throws down the gauntlet for audacious performance in a U.S.-bound, luxury, four-door sport sedan

Up Front

For automotive journalists everywhere, running out of superlatives represents a profound crisis of conscience. But every once in a while, along comes a car so entertaining, so unexpected that it transforms the habitually loquacious into babbling idiots. Consider me flabbergasted.

This muting wasn't the effect of a throbbing BMW, glitzy Mercedes-Benz, or even a rowdy American hopped up on muscle nostalgia. It wasn't at the wheel of relentless Japanese precision or even a four-leaf-clover-rare exotic supercar. No, I was flummoxed by the RS 4, a product of the little German luxury brand that apparently can, Audi.

The RS badge is Audi's answer to the more powerful, sportier versions of mainstream vehicles that BMW and Mercedes sell under the M and AMG badges, respectively—and at a hefty premium. The RS 4 is an up-tuned version of Audi's S4, itself an up-powered version of the A4 sedan. Confusing? Yes. But the result is an experience so good it's likely to leave you saying, "M who? AMG what?"

All this tuning yields a four-door sedan that performs like a Porsche 911, arguably the holy grail of driving. But the proposition isn't cheap. With a base price of $66,000, the 2007 RS 4 is between $12,000 and $15,000 more than the Cadillac CTS-V and Mercedes-Benz C55 AMG. It's also more than $17,000 more expensive than the outgoing 2006 BMW M3.

But that's all OK because the RS 4 is a better-looking, more agile and powerful car than all three. Not to mention that the upcoming redo of BMW's M3 is very likely to weigh in at a similar price point.

The double sixes get you an extensive grab bag of luxury goodies, including heated seats, dual-zone climate controls, power seats, headlamp washers, ultra-glam 19-in. wheels, bi-xenon headlamps, airbags for everybody, and on and on. My test car came with only one option, the $4,700 premium package that adds GPS navigation, dimming mirrors, Bluetooth, satellite radio, upgraded Bose stereo, power rear shade, and heated rear seats.

With a $720 destination charge and $2,100 gas guzzler tax, the total racks up to a sizable $73,520. Yikes! Luckily, it's all oh-so-worth it—even for nearly 75 large.

Audi says it hopes to sell about 1,000 RS 4 models this year. The company is desperately trying to claw market share and brand prestige away from its German rivals. That's undoubtedly a tall order, even if the company has no trouble standing shoulder-to-shoulder with BMW and Mercedes at home and around the world. Even at such low volumes, thrilling cars like this one are sure to generate buzz and push the company further in the right direction.

Power comes courtesy of a 4.2-liter, naturally aspirated V8 that whips up 420 horsepower and 317 foot-pounds of torque. It revs to a stratospheric 8,250 rpm. That's right: high-high redline, 420 horses, no turbo in sight.

But it couldn't matter less, because in any gear the engine just gives and gives and gives like a cross between Mother Teresa and Evander Holyfield. Even said combo probably wouldn't be able to get from zero to 60 in 4.7 seconds or break from that speed to a full stop in a mere 107 feet without any fade whatsoever.

Fresh off the lot, the V8's growl is more technical than guttural. Press the dash-mounted "S" button, however, and the Valkyries will indeed emerge. That button opens valves in the muffler and quickens the throttle response of the six-speed manual, but also takes the engine's tone to monumental crescendo.

The RS 4, like all Audis, is equipped with quattro all-wheel drive. But to eke out more performance, engineers tweaked the differential from a 50-50 split to a 40-60, giving the rear wheels a significant emphasis.

You don't turn in the RS 4. It slices through corners with geometrical precision. You point; it goes. It's by far the best steering in any Audi, and, in my opinion, seriously rivals leader BMW. Engineers must have made a Faustian deal with the Devil to get dynamics like this.

The other notable dash-mounted control is the electronic stability-control switch. Press this once and say adieu to traction control. That's nothing too special. Press and hold the button for three seconds and electronic stability is fully and utterly disabled. Call this insanity mode, as it makes it easy to induce rally-style slides.

Fellow German Kant would be proud. The RS 4 is a perfect illustration of the categorical imperative. In other words, thanks to the near-perfect tuning and abundant power, excessive speed is as justified as it is necessary. (To no avail, I tried to explain this to the New Jersey state trooper who pulled me over and ticketed me.)

Outside, the RS 4 stands beefier than other Audis. The fenders have, like the performance, been maxed out. Shark-gill vents on the side of the front bumpers are low and sharp without being overly aggressive. The trunk features a nearly invisible integrated spoiler that's as classy as it is discreet.

Inside you'll find a standard, luxe Audi interior: comfortable, extremely well put together, and uncomplicated. Audi's MMI navigation and audio interface is easier to use and nicer to look at than competing systems from BMW and Mercedes-Benz. RS accents include supremely supportive seats, carbon trim, and a sporty stick shift. All is bathed in a sexy red glow.

The RS 4 is rated to get between 14 and 21 mpg. I wouldn't count on getting anything nearly that high, though. This car lives to be pushed hard and thrown around even harder. I averaged around 10 mpg but, then again, the cost seems trivial for the sheer fun.

Buy It or Bag It?

I've driven a fair number of Audis lately, including the diminutive A3 and stately A8. The RS 4 is easily my favorite of the lot. Surely the best sign for Audi is that after driving it, I found myself thinking about more affordable editions and wondering if I could find some corollary joy in them.

What's more, the inevitable game of "I would buy this over…," comparing a long list of cars, both direct competitors and otherwise, was a total wash in the RS 4. That's because, all things being equal, I couldn't think of any other car I have recently driven that I would take for everyday pure fun over this Audi. That's including a $185,045 Aston Martin DB9 Volante with a 5.9-liter V12 and James Bond bravado.

Unfortunately, all things aren't equal and budgets are a fact of life. The RS 4 is more than worth the premium over the competitors I mentioned above. In fact, since there's not yet an RS 6, I'd throw in an RS 4 test drive if you're considering getting the bigger, badder BMW M5 or Mercedes E55.

But be forewarned, to drive one is to want one. Uncontrollably so. So if you really can't afford it, stay far, far away.
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