Inside the Latest Supercar From Mercedes-Benz
By Andreas Stahl
The fastest, most powerful — hell, the most outrageous — series production road car to hail from Mercedes-Benz's storied AMG performance division is finally here: the 2009 Mercedes-Benz SL65 AMG Black Series.
The latest in a line of performance cars to wear the increasingly revered Black Series badge, this new coupe with its 670-horsepower twin-turbocharged 6.0-liter V12 picks up where the soon-to-be discontinued SLR McLaren coupe leaves off. It provides supercar performance, highly individual exterior styling, a sumptuous two-seat cabin and guaranteed top-shelf exclusivity thanks to a $300,000 price tag.
A Very Limited Edition
To be produced in a limited run of just 350 (200 of which are bound for North America), the 2009 Mercedes-Benz SL65 AMG Black Series is proof Mercedes-Benz is now more determined than ever to mix it with the supercar elite, and not only with the odd homologation special like the old CLK GTR but also with an extended range of high-priced performance cars based on existing AMG models.
Up until now, details of the new coupe have been vague at best. In a bid to quell speculation, however, the German carmaker has come clean on its most radical road car ever, allowing access to the SL65 AMG Black Series during a session at the Mas du Clos circuit in France.
Based upon the SL65 AMG, this latest Black Series model follows the lead of the earlier SLK55 AMG and CLK63 AMG Black Series with a heavy focus on weight-saving and extensive alterations to the mechanical package, all aimed at creating a car worthy of filling the void soon to be left by the exiting SLR. It also functions as a test bed for developments slated for Mercedes-Benz's upcoming SLC — a car described by insiders as the spiritual successor to the iconic 300 SL, complete with gullwing doors, which is due out in 2011.
Bigger Turbos
The engine is a tuned version of the standard SL65 AMG's potent twin-turbocharged 6.0-liter V12. Running larger turbochargers, a bigger intercooler and revised exhaust, output has been bumped up by 57 hp to 670 horsepower at 5,400 rpm. Torque remains at 738 pound-feet between 2,200 and 4,200 rpm, and apparently it's actually limited from peak output claimed to be in the region of 885 lb-ft in the interests of ensuring the life of the drivetrain components.
Harnessing it all is a reworked version of Mercedes-Benz's aging five-speed automatic gearbox complete with remote shift paddles mounted on the back of the steering wheel. It's the only existing Mercedes-Benz gearbox capable of handling the engine's prodigious torque load, and it has been programmed with AMG's latest Speedshift software that provides four different shift programs: C (comfort), S (sport), M1 (manual) and M2 (an alternative manual mode that is claimed to shift up to 25 percent faster and with a more aggressive action than M1).
It also gets a double-clutch function that introduces a hearty blip of the throttle during downshifts for quicker gearchanges, added chassis stability and a smoother transfer of power under heavy braking. "We're conscious that many customers will want to take their car to the track," says Tobias Moers, AMG's development boss. "The new gearbox setup has been developed with this in mind."
Being a Mercedes-Benz, the Black Series has an impressive array of electronic driving aids. The specification sheet includes the latest in ABS, brake assist and stability control — the latter of which offers the driver a choice of three distinct modes, either standard, sport or completely disengaged. AMG has also seen fit to provide the SL65 AMG Black Series with a limited-slip differential.
Supercar Stats
With an impressive weight-to-power ratio of 6.15 pounds per horsepower and just about every electronic and mechanical traction-enhancing feature in the book, how quick is the new ĂĽber SL in a straight line?
Moers says validation testing is not yet finalized, but even at this early stage he is confident enough in the SL65 AMG Black Series to divulge that 0-100 km/h (62 mph) acceleration will be achieved in "less than 3.9 seconds." It doesn't end there. While the results remain unofficial, Moers also puts acceleration to 200 km/h (124 mph) at "below 10 seconds" and acceleration to 300 km/h (186 mph) at "inside 30 seconds." Top speed is limited to 320 km/h (199 mph). "It's more a precautionary measure with the tires than any concern with the car's aerodynamics," explains Moers.
Hinting at the new car's dynamic ability, Moers claims the SL65 AMG Black Series is "as fast, if not faster than the SLR" around the NĂĽrburgring, where much of its development has taken place in recent months. "In optimal conditions it should be possible to lap the Nordschleife in under 7:46," he says.
A Chassis To Match the Engine
The suspension incorporates lots of aluminum components, and while it shares its basic design with the SL65 AMG, Moers describes it as "all new." The ride height, wheel alignment, camber curves and damping rates are all adjustable, like those of the earlier SLK55 AMG and CLK63 AMG Black Series. New front suspension geometry also alters the ratio of the steering, making it 8 percent more direct than the SL65 AMG, and promises greater precision and sharper responses than any existing AMG model.
The car's track dimensions are dramatically wider, increased by 3.8 inches up front and 3.3 inches at the rear. The result is a truly aggressive stance that is further enhanced by purposeful-looking 19-by-9.5-inch and 20-by-11.5-inch OZ forged-aluminum wheels wrapped with 265/35ZR19 (front) and 325/30ZR20 (rear) Dunlop SP Sport Maxx GT tires.
In keeping with the track-biased thinking behind the new car, both the standard SL65 AMG's ABC (active body control) and AirMatic air springs have been binned. "On a car like this, there is no need for them," contends Moers. The brakes, meanwhile, are the largest AMG has ever applied to a road-going model, with giant vented and cross-drilled 15.4-inch steel rotors grabbed by six-piston calipers up front and 14.2-inch rotors with four-piston calipers at the rear.
Not Just an AMG Body Kit
The striking exterior of the SL65 AMG Black Series was created at AMG by its design boss, Claus Hieke. There are strands of the standard SL65 AMG's familiar DNA in various sections of the body. However, the visual link between the two is rather tenuous. The only features shared with lesser versions of Mercedes-Benz's upmarket roadster are the shape of the grille, headlamps, windscreen, mirrors, doors and taillamps. Everything else has been heavily reworked in a process that clearly places function over form.
At the front, gaping air ducts are mounted low on a heavily reworked bumper complete with an integral splitter to direct cooling air into the engine bay. They are accompanied by two sizable vents in the top of the hood, along with additional ports behind the front wheelwells — each of which serves to extract hot air away from the front end. Then there are the wheel flares. Like the shoulders of a heavyweight boxer waiting to unload a knockout punch, they're full of attitude.
The real highlight, though, is the roof. AMG replaced the standard SL65 AMG's folding aluminum hardtop with a fixed structure that incorporates new rear-quarter windows and a slightly larger rear window. It helps provide the car with a completely new character, while further back is a reshaped trunk lid housing a retractable spoiler that motors out by 4.7 inches on two supporting members to provide additional downforce at 75 mph.
The body construction is truly high-tech. Every panel apart from the aluminum doors is made of lightweight carbon fiber. The result is a curb weight of 4,123 pounds, a substantial 551 pounds less than a standard SL65.
Italian Performance, German Quality
One thing you should be able to count on is longevity. Like every other Mercedes-Benz model, the SL65 AMG Black Series has undergone an arduous development process, including an exhaustive 30,000 kilometers (18,641 miles) of circuit testing, some 15,000 km of which has taken place at the Nordschleife alone. "We've also run it in Death Valley and in Arjeplog," says Moers, referring to Mercedes-Benz's traditional hot- and cold-climate testing environments.
A total of 10 prototypes were built during the car's 18-month development process, at least two of which have been used to certify various crash regulations. European versions of the new car receive seatbelts anchored at the B-pillar and go without side airbags. Tougher side-impact regulations here, however, mean all U.S. versions will retain the standard SL65 AMG seats with integral seatbelts accompanied by side airbags.
Production of the SL65 AMG Black Series will take place in Mercedes-Benz's Bremen plant and the recently expanded AMG Performance Studio workshop in Affalterbach in Germany — the former supplying built-up chassis complete with driveline, with the latter responsible for the body and interior.
Mercedes-Benz is already holding more than 50 paid-up deposits for the 2009 Mercedes-Benz SL65 AMG Black Series from North American customers, leaving fewer than 150 of the planned 200 cars destined for these shores still up for grabs. On the strength of what we've seen so far, don't count on the remaining few staying unaccounted for for much longer.
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