Road Test

In the Swabian region of Germany, understatement is a way of life. When something is very good, they shrug their shoulders and murmur "nicht schlecht," not bad. There was a lot of that going around when we toured the AMG factory in Affalterbach, and drove three new AMG models at the Hockenheim racetrack. Due to go on sale in the United States this fall, they increase the AMG-enhanced lineup from two models to five. And there isn't a dog in the pack.

The heart of any AMG automobile is the engine: hand-assembled and signed by the craftsman who created it. The three new vehicles, the S 55 sedan, the CL 55 coupe, and the CLK 55 coupe, share the same powerplant; the 5.5L twin-plug engine currently found in the E 55 and the ML 55. The all-aluminum powerplant has a bore of 97mm and a 92mm stroke, achieving a near "square" dimension, ideal in a road car engine. Such a configuration is the best balance between allowable valve size and piston speed. Oil sprayed onto the underside of the pistons helps cool them, while the 50 percent reduction in piston-ring tension decreases the internal "drag" of the engine, improving fuel economy as well as unlocking power.

The biggest gun in the lineup is the S55 AMG, a steroid-laced version of the top shelf four-door S 500 sedan. The 5.5-liter engine, as fitted into the S55 develops 360 horsepower at 5500 rpm. With 391 lb-ft of torque at 3150 rpm and maintaining plateau flatness until 4500 revs, the big guy steps away smartly, 60 mph showing in a tick under 6 seconds, so says AMG. The tachometer wastes little time swinging to the 6000 rpm redline when the five-speed automatic transmission smoothly snaps into the next gear. Riding on 19-inch rubber, top speed is electronically limited to 155 mph, as it is on all AMG products. Exceptionally roomy, the complex interior is a wonderful environment to watch the world whisper past. The AMG mods strip away some of the intrinsic, insulating nature of the auto and sends more information to the driver. So when you dive into that corner hotter than planned, the S55 will more clearly communicate the laws of physics. The exhaust note is a rich, deep V-8 rumble, rising to a snarl when the tach needle lives in the upper range, reason enough to drive with the windows down.

The CL55 AMG is the high-end coupe model, a direct relative of the S55. With identical power ratings as the sedan, its performance is on a par with its stablemate. With discreet body additions front, rear, and on the rocker panels, the elegant lines ooze presence squared. While rear-seat room is sparse, front occupants are coddled in fragrant leather and polished woods. Not a bad place to be as you dive into the first turn at Hockenheim racetrack, or your favorite sweeper on the way home. Fitted with Mercedes' ABC stability program, the suspension resists body motions that could be perceived as excessive. Body roll, front dive, and rear squat under heavy throttle are all dampened to minimize discomfort. Under hard cornering, the weight of the vehicle becomes apparent, the suspension working hard to reduce oversteer. After coming into the pits after repeated hot laps on the track, the smell of hard-working brakes reminds you that the CL is no lightweight.

An AMG Mercedes DTM race car poses with its street cousin, the CLK55 AMG on the front straight at the Hockenheimring. The 450-horse 4.0L V-8 is bolted to a tubular grid-type frame to ensure rigidity as well as driver safety. A six-speed, sequential transaxle gearbox snaps off full-throttle upshifts with lighting speed.