Sport leicht, or sport and lightweight. Despite the two-plus-ton heft of Mercedes’ big boulevardier, that’s what SL has supposedly stood for ever since the car debuted in the ’50s. Now in its sixth generation, the SL promises to be more car than ever: more powerful, more efficient, and more light.
Adding power was the easy part. The SL550, which will be the first of the updated SLs to go on sale, will be powered by Mercedes’ new 4.7-liter twin-turbo V-8. The direct-injected engine makes the same numbers here as it does in the CL550: 429 hp at 5250 rpm, 516 lb-ft at 1800. Those figures represent increases of 47 hp and 125 lb-ft compared to the outgoing SL550’s 5.5-liter V-8. The engine is backed by a seven-speed automatic transmission and now gets standard stop/start functionality. Mercedes predicts a 0-to-60-mph time of 4.5 seconds, 0.8 better than its claim for the last SL550, although runs that begin with the engine off will take a few extra tenths. Since the company’s estimates are generally conservative—we hit 60 in 4.8 seconds with a 2011 SL550—figure on something closer to four seconds flat. And then realize that’s as quick as the outgoing SL63.
Some of this newfound quickness will be thanks in no small part to a reduction in weight. The 2013 SL550 uses the company’s first all-aluminum body in a series-production model, which is claimed to make it 275 pounds lighter than the car it replaces. If you’re having trouble imagining the weight difference, Dr. Thomas Rudlaff, who was responsible for the aluminum shell, puts it into perspective: “The effect is as if a large passenger has stepped out of the car.” (Keep the fat American jokes to yourself.) We should mention that some high-strength steel tubing is used to reinforce the A-pillars, lest they accordion in a crash. The suspension also uses lightweight pieces, and Active Body Control, M-B’s adaptive suspension, continues to be an option. The SL will switch to electric power steering, which should improve efficiency while hopefully retaining some semblance of feedback.
All of this weight loss is despite a dimensional gain. The 2013 car is 1.4 inches longer, 2.2 inches wider, and rides on a 1-inch-longer wheelbase. Front and rear track also are increased. Mercedes says this all helps create a larger cabin. We had no complaints about the interior room before.
Thanks to: Car and Driver
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