It doesn't take long for the AMG tuning wizards to work their magic on new Mercedes-Benz products. Less than two months after the all-new SL-Class roadster debuted at the 2012 Detroit auto show, Mercedes is introducing the high-performance 2013 Mercedes-Benz SL63 AMG. Following the established pattern for all AMG-massaged products, the SL63 receives a more powerful engine, improved chassis dynamics, and racier body components than the car on which it’s based.
For the 2013 SL63 AMG, the engine in question is the M157 mill also found in several other recent AMG models. It is a twin-turbocharged 5.5-liter V-8 tuned in the SL63 to produce 530 hp and 590 lb-ft of torque. The engine will rocket the SL63 to 60 mph in a claimed 4.2 seconds, with top speed electronically restrained to 155 mph. If buyers select the AMG Performance package, output rises to 550 hp and 664 lb-ft, reducing the 0-to-60-mph time to 4.1 seconds and nudging the speed limiter up to 186 mph.
The regular SL550, by contrast, makes do with a twin-turbo 4.5-liter V-8 with 429 hp, and takes a claimed 4.5 seconds to reach 60 mph. That SL is limited to just 130 mph.
Between the engine and rear wheels is Mercedes' AMG Speedshift, a seven-speed automatic transmission that uses a wet clutch pack in place of a traditional torque converter and sports four shift modes. The gentlest setting, Controlled Efficiency (C), also activates the SL63’s engine stop-start system to help save fuel when idling. Upgrading to the AMG Performance pack also includes a locking limited-slip rear differential for more traction.
In addition, Mercedes says the new engine and other additions like stop-start make the 2013 SL63 AMG about 30 percent more fuel-efficient than the old car; the 2012 SL63 scored EPA ratings of 12/19 mpg city/highway.
Upgraded ChassisComplementing the extra motive force is an assortment of chassis updates. Above all, Mercedes-Benz notes that the 2013 SL63 is at least 275 pounds lighter than the outgoing model, in part because the new roadster makes extensive use of aluminum in its chassis and suspension, in addition to bits of carbon fiber and magnesium to help save weight in other areas.
The SL63 is brought to a halt by massive AMG brakes, 15.3-inch discs gripped by six-piston calipers in front and 14.2-inch rear discs grabbed by single-piston calipers. Buyers can upgrade to higher-performance ceramic brake discs like those found on the SLS AMG supercar; opting for the AMG Performance treatment paints the brake calipers red.
The SL63 rides on an AMG sports suspension based on Mercedes' ABC adaptive suspension and switchable between Comfort and Sport modes. Compared to the regular SL550, the AMG model has thoroughly revised suspension tuning with significantly more negative camber. The roadster also gets AMG's speed-sensitive steering assist; it has a faster ratio than in the SL550, and the assistance changes in concert with the suspension setting. Finally, AMG adds its three-mode stability control, which has a more-lenient "Sport Handling" setting.
Pieces of FlairTo complete the transformation, AMG blessed the SL63 with a new front fascia and splitter, a black decklid spoiler and rear diffuser, chrome quad exhaust tips, several V8 BITURBO badges, and a unique front grille. The standard wheels are lightweight 19-inch units, and buyers can upgrade to forged AMG Performance Studio wheels that measure 19 inches front, 20 inches rear. The two-place cabin scores a flat-bottom AMG Performance steering wheel, the Racetimer performance meter screen, leather-covered AMG sport seats with carbon-fiber backing, and the AMG Drive Unit buttons that allow selection of suspension and transmission modes.
The 2013 Mercedes-Benz SL63 AMG will make its public debut at the Geneva Motor Show in March. Rumors suggest the car may be followed by an even more powerful SL65 AMG, possibly with a turbocharged V-12 engine. The new SL63 reaches showrooms in the U.S. market in mid-July 2012, about two months after the regular SL550 goes on sale here.