German Car Forum

It’s five and a half feet long. It weighs 8.8 pounds. Height of an adult female, weight of a gallon or so of gas—these are the critical dimensions of the carbon-fiber driveshaft running between the engine and the rear-mounted transaxle in the new Mercedes SLS AMG. We note this here because, despite the car’s retro-gullwing looks, the SLS is utterly bleeding edge—both in terms of its technical attributes and what it represents for Mercedes’ in-house tuner. It is not simply a Mercedes with bigger wheels and a breathed-upon V-8 or V-12. It is, down to its churning carbon-fiber core, AMG’s first dedicated automobile and the very antithesis of the overly complex and overweight half-million-dollar Mercedes SLR McLaren.
“The SLS is a serious super sports car,” says AMG chief of development Tobias Moers before taking a shot at the SLR, a carbon-fiber-bodied car that still managed to weigh in at 3858 pounds. “Our SLS weighs only 3572 pounds,” he says, nearly 300 pounds lighter than the McMerc. Keeping the 182.6-inch-long, two-seat SLS’s mass in check is its entirely aluminum construction (save for that driveshaft and steel A-pillars), a first for Mercedes-Benz. The aluminum structure weighs just 531 pounds, Mercedes says.
The most distinctive aspect of the SLS’s appearance is, of course, its roof-hinged gullwing doors, an homage to the iconic 300SL Gullwing. But AMG personnel took pains to point out that the doors are the only thing the SLS has in common with the 300SL. “We do not build a retro car at all!” AMG boss Volker Mornhinweg explains sharply. “In fact, we think it is the most advanced super sports car you can buy today.”
Those gullwing doors look spectacular. Unlike with the original SL, where one had to slide over a wide sill because of the space-frame structure underneath, it’s easy to access the SLS’s cabin. There’s only one issue: Riders need long arms to reach the distant handles at the bottom of each door to pull them closed.
The interior is simple and uncluttered, much like a current SL roadster’s. While the car’s structure is a pure AMG design, most of the parts, except for the shifter, are from the Mercedes bin. The instrument cluster is clear and easy to read, and we love the round HVAC vents. The center console has an aluminum finish, with carbon fiber an option.
Press the starter button on the center console, and the now-familiar, AMG-designed 6.2-liter V-8 awakens with an angry yelp. The idle is deep, and the revs rise and fall race-car swiftly. Code-named M159, the engine is basically a reengineered version of the M156 unit that’s fitted to AMG’s “63” models. The M159 comes with an all-new magnesium intake, forged pistons in place of cast ones, and optimized tubular exhaust headers. The engineers also switched from a wet sump to a dry arrangement, allowing the engine to be mounted lower to benefit the SLS’s center of gravity. The maximum output of 563 horsepower is delivered at 6800 rpm, and peak torque of 479 pound-feet comes at 4750 rpm.
In order to satisfy emissions standards—EU5, LEVII, ULEV—the Bosch ME 9.7 AMG engine management is set up to recharge the battery during deceleration. It’s another way of trying to eke out decent fuel economy, which, based on Mercedes’ European estimates, should equate to roughly 13 mpg city and 20 highway.
The SLS is the first Mercedes to use a new dual-clutch seven-speed transmission that was developed in conjunction with Getrag. This transaxle is mounted at the rear of the car and is connected to the engine by that carbon-fiber driveshaft. Perfectly executed blips of the throttle during downshifts not only make the shifts smooth, their bark could also break any nearby glass.

There are four driving modes to select via the snappily named “Drive-Unit” button on the center console, and these range from comfortable to extremely sporty. “C” stands for “controlled efficiency,” in which the car sets off in second gear. “S” (sport) rips off shifts that are 20 percent faster, while “S+” (sport plus) is again 20 percent quicker. “M” (manual) is fully 50 percent faster than “C.” A launch-control system is also on hand [see caption on next page].
Since we’re at a racetrack and not doing maximum acceleration runs, I decide to put the transmission selector into manual, which automatically moves the stability-control system into ESP sport. This allows for a higher intervention threshold but will hopefully save me from a close encounter with any scenery. And then it’s pedal to the carpet: The rear 295/30R-20 tires bite into the pavement, the rear end squats slightly, and the SLS jumps forward. The explosive acceleration is accompanied by a powerful, throaty engine note that hardens to a metallic wail above 4500 revs. All the way to redline, the only engine that responds better is the Ferrari 430 Scuderia’s fantastic V-8. Performance feels exceptional: We expect 0 to 60 mph in 3.5 seconds and the quarter-mile in 11.7, and Mercedes claims the SLS will continue on to a governed top speed of 196 mph.
Coming up to a corner, I brake hard and the nose dips before easing into the bend. The optional carbon-ceramic brakes, which are 15.8 inches in diameter at the front and 14.2 inches at the back, are powerful and responsive, and the power-assisted rack-and-pinion steering is easily the sharpest we’ve encountered in a Mercedes street car. As soon as I jump back on the throttle, the rear end slides a bit, but that oversteer is easy to control. The car feels well balanced, likely helped by a claimed weight distribution of 48 percent in front and 52 percent in back. Sitting so close to the rear axle also heightens the driver’s sense of riding on all that power.
Traction out of corners is impressive, aided not only by the traction-control system but by a mechanical limited-slip differential. The suspension is fairly conventional, with control arms all around. They’re forged aluminum, as are the steering knuckles and hub carriers. The faster we go, the more stable the car seems. At anything above 75 mph, the rear spoiler springs into action to maintain the front-to-rear balance; go below 50, and it recedes. “We don’t think it is necessary to use the spoiler as an air brake,” Mornhinweg says, in another sly dig at the SLR.
As well as being an extremely well-balanced and exciting sports car that’s more entertaining than an SL63 AMG and more rounded and coherent than an SLR, the SLS is, oddly enough, a very practical supercar. It has six cubic feet of trunk space, possesses no fewer than eight airbags, and is very comfortable. It will take its occupants shopping just as easily as it will bound cross-country. It just won’t come cheap: We’re told it will fill the price gap between the SL63 and the SL65 Black Series when it’s available next spring. Figure about $225,000.
During our drive, we couldn’t help but wonder if there is potential for an even lighter and more focused version of the car. There are, for instance, a couple of electric motors that are used to raise the door handles while opening the car with the keyless entry system and lower them when driving at more than 9 mph. They could go. And what about the power seats and the navigation system? We already know there will be upcoming roadster and hybrid versions of the car. Now how about an SLS Black Series?

2011 Mercedes-Benz SLS AMG - Second Drive - Auto Reviews - Car and Driver