The RS7 applies the full hot-rod treatment to Audi's A7 Sportback—the slinky five-door that arrived near the front edge of the sedan-as-coupe wave and added hatchback utility. With about 552 brake hp, the 2014 RS7 also happens to be the most powerful Audi yet offered in North America.
Like other RS products, the RS7 is pulled from the A7 line and hand-finished in Neckarsulm, Germany, by quattro GmbH—the VW Group subsidiary that is to Audi as AMG is to Mercedes-Benz. The RS7 is an anniversary car of sorts, marking 30 years since quattro GmbH was established to develop the original Audi Quattro coupe for World Rally competition and Pikes Peak. It applies three tenets that are guiding quattro toward better efficiency, according to CEO Frank van Meel: less weight, less displacement and Audi's cylinder on demand technology.
The RS7's 4.0-liter V8 starts with the same block as the S7 and various A8 sedans. Van Meel says it's the most compact turbocharged V8 in a production car, measuring just 19.5 inches from the 90-degree V's front to the rear. The intake side of the cylinder heads is on the outside, the exhaust on the inside, and the two turbos are tucked in the rear of the valley. Peak boost increases to 17.5 psi, compared to 12.3 psi in the S7 engine, and peak output increases accordingly: 552 bhp (SAE rating pending) and 516 lb-ft of torque, from 420 and 406 in the S7.
In the name of efficiency, the RS7 engine is equipped with both a stop/start feature and cylinder on demand. Audi's works like other variable displacement systems, closing valves on cylinders 2, 3, 5, and 8 and shutting off fuel when rpm remain below 3,500 and torque demand below 185 lb-ft. At a steady 62 mph, cylinder on demand reduces fuel consumption 10 percent, according to Audi, and should improve EPA ratings 5 percent. The RS7 will carry no gas guzzler tax in the United States. It gets the same eight-speed, torque-convertor automatic used in the A8, with expanded cooling capacity and different gear ratios. The lower gears are spaced closely for immediate response, and eighth is way overdrive at .667.
The all-wheel drive starts at a new center differential with a higher locking rate than those in other large Audis. The default torque split is 40 percent front, 60 rear, though the diff can direct as much as 70 percent of the power to the front wheels and 85 percent to the rear. A torque-vectoring control strategy uses the brakes to manage power at each wheel, while the rear differential actively distributes torque between the rear wheels. In a curve, for example, it will power up the outside rear wheel to help vector the RS7 through.
The RS7 is built from the same steel/aluminum unit body as other A7s, but lighter components lower curb weight 33 pounds compared to the S7. It generates 30 pounds more aerodynamic downforce in front thanks to a more prominent lip below the front bumper and positive downforce (as opposed to lift) in back—largely a function of reworked underbody shields.
The standard air suspension is active, adjusting spring and shock rates on the fly, according to conditions or the driver's setting. The upgrade—RS Sport Suspension Plus with Dynamic Ride Control—is a full mechanical system with steel springs. The only adjustment changes the diameter of the shock valves, for comfort, normal or dynamic modes. DRC's diagonally opposed pairs of shock absorbers are linked by hydraulic lines and a central valve. Cornering at speed, the valves increase oil flow in the shock at the deflected outside wheel almost immediately, keeping the body virtually flat. Initially only the air suspension will be available in the United States though Audi promises DRC at some unspecified point in the future.
DRC also includes a gear in the steering column that varies the steering ratio between 13:1 and 15.9:1 as a function of road speed or the driver's preference. The RS7 comes standard on 20-inch rims with 275/35-series tires. The 21-inch upgrade lowers the aspect ratio to 30 but all-season tires are not an option in either case.
One of the RS7's weight savers is a “wave” design for the standard steel brake rotors, measuring 15.5 inches in front and 14 inches rear with six-piston calipers. The disks' outer edge is machined with a unique scallop shape shaving unsprung weight 6.6 pounds. The carbon-ceramic option—available in North America when DRC arrives—sheds another 33 pounds.
For $104,900 and an $895 destination charge, the RS7 will come from Germany with an expansive array of standard equipment including LED headlights, four-zone automatic air conditioning, navigation with Audi MMI and a built-in wireless LAN. Several appearance, performance and safety options, including Bang & Olufsen audio ($5,900), head-up display, night vision and adaptive cruise control can add $30,000 to the base price—before DRC or carbon-ceramic brakes come to our market.
Audi hasn't specified exactly when the RS7 will arrive but it will certainly be here by fall. The United States has been the brand's largest market for the A7 and that trend is expected to continue with the RS7. Apparently we like this hatchback. The A7 line will expand to four choices in 2014 as the RS7 and the new A7 TDI, with its 428-lb-ft, 38-mpg 3.0-liter diesel, join the A7 and S7.
What's it like to drive?
Good, Jean Girard. Real good. The RS7 might come as close to being a true all-things-to-all-people, high-performance automobile as exists on planet earth.
Its drivetrain is suited to just about every purpose—even a blizzard, we'd venture, if you fitted legitimate winter tires. As automatic transmissions go, the RS7's is tier one, plus. The possibilities range from the casual, unobtrusive smoothness of a three-speed Turbo-Hydramatic to reaction time and shift speed approaching the best dual-clutch manu-matics. This torque-convertor box is better fit to the RS7's purposes than any DSG yet devised—quick, rev-matching downshifts with little backfire burps that sound like heaven and more smoothness, subtlety and comfort in trundle-about mode. It gives up nothing of consequence as a performance tool in a car of the RS7's size and heft and pays back fivefold as a transportation tool.
The first few gears are extra low. There aren't too many cars that are going to beat the RS7 out of the hole, no launch-control function necessary. Yet the RS7's most remarkable characteristic might be rolling acceleration—say, 50-100 mph. Floor the gas pedal leaving an entrance ramp and you're presented with a genuine holy-crap experience: smooth, instantaneous downshifts and turbine-style thrust that will push the corners of your mouth outward. The RS7 has the lungs and gearing to cruise all afternoon at a buck-fifty on the autobahn while your lunch mates sip machiattos in the back seat. At least with the standard air suspension.
The continuously adjustable air suspension will almost certainly work best for most drivers. There's a noticeable upgrade in body control when it's switched to dynamic mode, but ride quality remains smooth and acceptably comfortable in all circumstances.
The real fun, however, presents with the DRC sport upgrade. Here dynamic mode truly rocks—at least from the, um, dynamic perspective. This simple lightweight hydraulic system is among the best offered for keeping the body level. With DRC there is virtually no sway or lean in the RS7, no pitching or rolling, even with hard, unsophisticated jerks on the wheel, or loaded up close to one g in a curve, or going hard on and off the brakes.
It feels like a conundrum. Given the general satisfaction built into the Audi S7 and a steep price upgrade to the RS7, there aren't many practical reasons to buy the full sport model if you don't plan on getting really dynamic, and the DRC gets dynamic better than the standard air suspension. On the other hand, even in comfort mode on Germany's comparatively silken road surfaces, the DRC's ride falls on the stiff side. It might be too stiff for a comfortable cruise across the Ohio Turnpike. Machiattos will spill. While we appreciate the fun, it's fairly easy to see why Audi's product people in North America aren't clamoring to get the DRC here as soon as possible.
The same conundrum applies to the carbon-ceramic brake option; it will likely be a very expensive checkmark whenever it's actually offered in North America. Here, though, the payback for better fade resistance and a considerable decrease in unsprung weight isn't as dear as the stiff ride that comes with DRC. These ceramic brakes come very close in presentation—pedal feel, noise—to conventional cast iron or steel rotors, once they are up to temp.
One great thing about Audi Drive Select, particularly in the RS7, is that it lets you tailor various control strategies the way you like them. You can get the quickest throttle response or the most responsive shift protocol, and still dial back to a softer ride or less steering effort.
Steering may be the weak link in the RS7 though we wouldn't call it weak. From the performance perspective the optional variable rate rack is best again in dynamic mode. This drops the ratio about 20 percent with a fixed rate across the range, leaving the front wheels to turn at a constant rate with the steering wheel, regardless of the amount of input off-center. There's just a slight sticky, wooden feel to the way it feeds sensations to your hands. It has zero impact on the RS7's capability but feels slightly out of character with the general gracefulness in this big, wide speedster.
And the RS7 is big. As in the standard A7, the rear accommodations are truly comfortable—good seats and space approaching full-size sedans like the A8, 7-series or S-class. There's also 18.9 cubic feet of cargo space under the hatch, or an expansive 49 cubic feet if you flatten the rear seat. You won't get that in an A8. It all works to make the RS7 a faithful comfortable servant when you need one, and a ground-bound rocket ship when you want one.
Do I want one?
Why wouldn't you? The RS7 lacks nothing. It's big, very fast, great to look at and still useful in the practical sense. There's no gas-guzzler tax. If you can actually afford one, you'll get front-row valet treatment and smoke Camaro ZL1s, Boss 302s or 911 C2s at stoplights—on your way to pick up a new big screen at Best Buy. Our road test suggests if you take advantage of track opportunities, the RS7 will deliver as much challenge and satisfaction as any big sedan you can buy. Set full dynamic, with DRC, it's savage.
Of course the Audi S7 is a fine car, too, with plenty of V8 horsepower for $25,000 less. The upgrades in the RS7 are apparent and there are bragging rights and the S7's more finicky (in our estimation, less desirable) DSG transmission. But if don't plan on getting really dynamic, you might be as happy without the R.
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