Mercedes-Benz SLS AMG: The gullwing takes flight
Wed, 15 Jul 2009Before we reveal what it is like to hot-lap a prototype version of Mercedes-Benz's 6.2-liter V8-powered SLS around the 2.2-mile Sachsenring in eastern Germany, let us tell you one thing that puts the big rear-wheel-drive coupe into clear perspective.
The SLS, planned to get its first public outing at the Frankfurt motor show in September, is not based on any existing Mercedes model. Rather, it has been conceived, designed and engineered from the ground up in a no-compromise approach by the German carmaker's in-house tuning division, AMG.
“Every component is either unique or heavily modified from standard and has been chosen with a great deal of care and consideration,” says development boss Tobias Moers, with a grin of obvious satisfaction. “It's far from your average AMG model.”
The SLS can hit 62 mph in 3.8 seconds from a standstill.
That is obvious from the moment you draw the SLS's gullwing door closed with a big heave from overhead, press the starter button on the center console, draw the paddle shift on the steering wheel forward to select first gear and accelerate hard out of the pit lane, followed by the blare of an angry exhaust.
The new two-seater's exterior styling adheres closely to the overall shape of its spiritual predecessor, the gorgeous 300SL. However, the SLS is anything but a throwback. Its lightweight aluminum body is supported by a superstiff, state-of-the-art aluminum spaceframe that helps it achieve a 3,696-pound curb weight.
The 6.2-liter V8, mounted up front behind the front axle line, is related to the engine that AMG places in just about all of its road-going models these days, the M156. A raft of modifications make it lighter and livelier. There are so many changes, in fact, that the SLS's engine gets its own unique code name: M159. It kicks out 571 hp at 6,800 rpm, with 479 lb-ft of torque at 4,750 rpm--some 402 lb-ft of which can be tapped at just 2,500 rpm.
Channeling the drive back to the rear wheels is the first-ever dual-clutch gearbox for Mercedes. The seven-speed unit has four distinct shift modes as well as a race-start function, and it departs from AMG convention in being mounted at the rear in a transaxle. It's an arrangement that helps provide the SLS with a near-perfect weight distribution of 48 percent front/52 percent rear.
It's a potent combination that sees the SLS hit 62 mph from standstill in 3.8 seconds. That's impressive, and it would be even sharper with a more aggressive final drive ratio. It's through the gears, though, where the new Mercedes really comes alive; the sprint to 124 mph is achieved in less than 10.0 seconds, according to Moers. Flat-out, it tops 195 mph.
For all the severity of its acceleration, though, the SLS is remarkably fluid in its actions. The power-assisted steering is light, but there's enough life in it to urge you to push hard through corners, because you're always aware of what the front end is up to--not something you could say about AMG's other supercar of the moment, the SL65 Black Series
The interior of the SLS is shown.
You can sense the low moment of inertia--the upshot of AMG's efforts to concentrate as much weight around the center line as possible--in the wonderfully neutral nature of its handling.
When you do edge past the high levels of adhesion, the SLS's chassis--a combination of traditional double wishbones all around, without any superfluous active-suspension gimmickry of any kind--allows you to dabble with oversteer. Turn off the ESP, and lurid tail-out slides are there for the taking in appropriate conditions.
The traction is perhaps the most appealing part of this car's dynamic repertoire. The SLS stomps out of corners with extraordinary rear-end purchase and incredible poise, feeling more like a rear-engine car than one whose engine sits up front.
To say that the SLS is merely good is to do it no justice. It is spectacularly good--solid, fast, agile and entertaining in a way that no modern-day Mercedes model can claim, the McLaren-built SLR included. AMG's decision to look beyond any existing Mercedes model when developing the new coupe has clearly paid handsome dividends. After 10 laps of the Sachsenring, we have no doubt that Aston Martin, Audi, Ferrari, Lamborghini and Porsche all have a potent new rival on their hands.
By Greg Kable