Super sedan spin

2007, Audi, RS 4

LEIPZIG, Germany -- With that deep-throat buzz of a powerful V8 in the engine bay and four high-performance Pirelli P Zero tires singing a speed song on Germany's A14 autobahn near Leipzig, the aero-slick RS 4 by Audi of Germany rules the asphalt on a triple-digit pace.

This sleek super sedan, derived from Audi's A4 compact series, skews toward that rare and sporty realm of refined European muscle cars with its big V8 aboard plus a six-speed manual gearbox.

This sleek super sedan, derived from Audi's A4 compact series, skews toward that rare and sporty realm of refined European muscle cars with its big V8 aboard plus a six-speed manual gearbox.

It's incredibly quick -- under five seconds from stand-still to 62 mph and on to 125 in only 16.6 seconds, with the top speed electronically capped at 155 mph.

Despite a capacity for super speeds and stunning bury-you-in-the-seat acceleration, the RS 4 also shows us at lesser speeds that it's a curve-craving machine which seems to defy the inertial laws of physics.

Weight-saving aluminum components make the suspension, tuned and tweaked for precise and predictable action, feel light and lively, while Audi's Quattro system for traction at every wheel sets up the tire grip of a sidewinder snake in sand.

It's downright wicked when sent into a wiggle set -- which explains our exuberance while steering the RS 4 on a curvy backroad course tracing the Leiberger River through villages of Polkenberg and Kossern to Grimma.

There's so much muscle with this car, such corner-cutting agility, and the capability to virtually fly across the landscape.

All of these attributes apply to the RS 4, yet the car camouflages well to all but educated eyes, as it essentially resembles the taut yet sedate shape of Audi's A4 sedan.

Theme for RS 4's exterior design is a fluidity of lines drawn in rectangular format but capped by an arching canopy over the cabin with low-slung windows and side pillars muted to create the impression of a sleek coupe.

Still, you can't miss the in-your-face design of the prow with a gaping grille in trapezoidal format rimmed by chrome and filled with black mesh but streaked by two horizontal fins.

Two additional air-intake scoops stud the smooth body-color aero fascia below.

Projector beam lens of adaptive bi-xenon headlamps flank the front grille behind clear polymer shields in narrow rectilinear housings.

Fender flares made from aluminum bulge to cover the RS 4's stretched track width, which extends for 1.5 inches wider in front and 1.9 inches in back.

Side panels are chiseled almost sheer for slab doors and underscored by side skirts, yet a character line notched low on each side seems to swing upward in swift movement toward the tail.

A discreet spoiler lips over the trailing edge of the trunk, while in the lower fascia there are two oval exhaust pipes that subtly convey the message that this is indeed a car of contentious strength.

Wheels also play the performance tune.

They're split seven-spoke rounds of cast alloy measuring 19-by-9 inches and capped by 235/55 tires rated for top speed.

The suspension, intensive in lightweight aluminum components, is independent at all corners and dropped 1.1 inches lower than A4 iterations.

In front, the multi-link design with stabilizer bar and coil springs promotes agility but also manages to isolate road harshness and noise. In back there's a wishbone with stabilizer bar and coil springs.

Audi then adds Dynamic Ride Control (DRC), a mechanical system hydraulically connecting the diagonally opposite front and rear dampers with a gas-charged reservoir. Movement of fluid through this linkage will stiffen or soften the shocks in order to counteract any roll or dive or pitch of the car during handling maneuvers.

The system sets up a compliant and forgiving ride quality which, in European touring car tradition, encourages an active style of driving. Yet it's stiff, and you feel undulating nuances of a road surface translated through suspension and steering to driver's hands and body.

Steering, using a rack and pinion arrangement, is direct and incredibly quick with power assistance that varies the degree of boost according to road speed.

Massive brake rotors run to 14.4 inches up front and 12.8 inches in back, and they rely on electronic and computerized links to tame the tires. Anti-lock brake (ABS) controls are standard, along with electronic braking assist (EBA), plus Audi's anti-slip regulation (ASR) throttle checker. All of these acronyms are included as control components of the standard electronic stabilization program (ESP) that stems lateral slippage and skidding.

The RS 4 also employs Audi's Quattro all-wheel-drive (AWD) system, a permanently engaged device which distributes the engine's power to all wheels. Using a Torsen center differential with 40/60 rear-biased torque split, the smart mechanism automatically shifts the majority of all engine torque to whichever wheels, front or rear, attain the best bite of traction.

Now check out the RS 4 muscle package.

It's a new aluminum 4.2-liter V8 with Audi's remarkable FSI (fuel straight injection) technology applied.

Power rips to 420 hp at 7500 rpm with max torque of 317 lb-ft at 6000 rpm -- and this plant revs way up to 8250 rpm.

Sole shifter is a six-speed manual, which works through a console-mounted sporty stick.

In the spacious cockpit there are Recaro sport seats up front with big side bolsters to pin your body in place.

Silk Nappa leather coats these buckets, with multiple-position power controls on tap and heat elements added.

Inlay trim consists of racy carbon fiber.

Standard cabin gear includes a twin-zone automatic climate system, power glass sunroof, multicolor information display with lap timer, plus Parktronic backup warning device.

The optional Premium Package nets DVD-based Navigation and a six-disc CD changer, auto dimming mirrors, memory for driver's seat and side mirrors, rain sensors on wipers, an upgraded Bose sound kit with satellite radio service, heated rear seats, power rear sun shade and Bluetooth connectivity.

The price for RS 4's speed pleasures is dear: Audi sets the MSRP at $66,000, but then you must tack on a $2,100 gas-guzzler tax, and the Premium Package adds $4,700 more.

By Bob Plunkett

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Images of the 2007, Audi RS 4

2007 Audi RS 4
2007 Audi RS 4
2007 Audi RS 4
2007 Audi RS 4
2007 Audi RS 4
2007 Audi RS 4
2007 Audi RS 4
2007 Audi RS 4