The SL55 AMG's supercharged V8 is extremely strong, but it's also smooth and quiet. This car's acceleration is breathtaking, with 493 horsepower motivating just 4200 pounds. The SL55 AMG is capable of accelerating from 0 to 60 mph in about 4.5 seconds. Peak torque of 516 pound-feet is available from 2750 rpm. The V12-powered SL65 AMG will scream from 0 to 60 in 4.2 seconds.
The SL65 AMG starts with a bored and stroked 6.0-liter V12 and then turns up the turbo boost from 1 atmosphere to 1.5 (that's from 14.5 psi to 22 psi). Forged pistons, a precision-balanced crankshaft, stronger bearings and oil-spray cooling all help deliver 604 horsepower and 738 pound-feet of torque. The SL65 AMG can accelerate from 0 to 60 in about 4.2 seconds.
The SpeedShift five-speed automatic transmission in the SL600, SL55, and SL65 is superb, with nearly imperceptible shifts up or down. Pulling the selector toward the left causes the transmission to shift down to the next gear. Or the driver can use shifter buttons on the steering wheel: right for up, left for down.
The seven-speed automatic in the SL500 keeps its engine humming closer to optimal rpm at all times. Mercedes-Benz claims the SL500 reaches 60 mph 0.3 seconds quicker than it would with the other models' five-speed. The seven-speed undoutbedly also contributes to the SL500's EPA rating of 16/23 city/highway, significantly better than any of its brethren.
ABC (for Automatic Body Control) active suspension lets the SL corner with authority, even though its tires are smaller than those on a 911, Corvette, or Viper. The computer controlled system uses a hydraulic piston above each spring to add stiffness as needed, reducing body roll by 68 percent. A Sport switch lets the driver limit body roll even further, eliminating 95 percent of it, while still delivering a silky smooth, quiet ride.
The SL roadster is packed with electronic wizardry that works amazingly well: electronic throttle control, antilock braking (ABS) with electronic brake-force distribution (EBD), electronic traction control and electronic stability control. These systems have been added to other Mercedes-Benz products in recent years, but the SL gets a fully electronic braking system. If it didn't do anything else well (and it most certainly does), the SL would have to go down in history for this development alone.
The SL's electronic braking system runs on very high hydraulic pressure, but the pedal feels normal no matter how hard you stop, and the ABC suspension won't let the car take a nosedive. While the pedal feels perfectly normal under all braking applications, the system works quicker and faster than ordinary vacuum-assisted, low-pressure hydraulic braking systems and can proportion braking effort to each of the four tires depending on traction and yaw conditions, working hand-in-hand with the ABS, traction and stability systems as well as the active suspension. These electronic features mean that this SL will corner and brake faster and harder and flatter than any previous SL while providing a huge envelope of protection against driver error and changing traction conditions.
The SL65 AMG stops with the largest brakes of any SL: 15.4-inch discs in front and 13.7 in the rear. The front discs are internally ventilated and perforated for cooling and feature a new two-piece, compound rotor-and-hub assembly made of cast iron and aluminum that allows additonal thermal expansion. Eight-piston fixed calipers grab the front discs while four-piston fixed calipers suffice in the rear. Wheels and tires are 255/35ZR19 front and 285/30ZR19 rear. A limited-slip differential maintains the rear tires' grip on the pavement.
Drive any SL on any mix of tarmac, gravel, mud, water, ice or snow and the onboard systems keep the car on the straight and narrow with very little driver input. After five or six hours of fast driving on challenging roads, this car will make you feel like one of the masters of the universe. It's that good. It doesn't have the gut-level appeal of a Viper, Corvette, or Porsche, but the SL is far more comfortable and luxurious than any of them. It seems like the faster you go, the greater feedback you get from the road. We noticed an increase in road vibration at 95 to 100 mph. Next Page