As with its underpinnings--an amalgam of modified C-Class sedan chassis pieces and E-Class suspension and brake components--the CLK's exterior uses design elements from other Mercedes lines to create a uniquely graceful presence. In particular, the four ovoid headlamps, which made their debut on the E-Class, lend an unmistakable Mercedes touch at the front, and the sweeping arc of the rearmost roof pillars sweetens the whole shape.

The CLK320 is powered by the first V6 in Mercedes-Benz history. It comes allied with an "intelligent" 5-speed automatic transmission. It's a superb combination that's capable of propelling the 3,240-pound CLK320 from 0 to 60 mph in less than seven seconds.

The new 3.2-liter engine is the most salient of the many technological features that distinguish this new rear-drive offering from Mercedes-Benz. Although it makes respectable horsepower and even more respectable torque--232 pound-feet--its real strengths are low weight and exceptionally good emissions performance. A lighter engine reduces weight over the front wheels, which improves balance and handling.

This engine weighs just 330 pounds. Its low weight was achieved through extensive use of lightweight materials: an aluminum block, cylinder heads and pistons, silicon aluminum cylinder liners, magnesium valve covers, and an aluminum oil pan.

The new Mercedes-Benz 3.2-liter V6 meets the requirements for California's tough Low Emissions Vehicle (LEV) classification. This unusual combination of plentiful power and low emissions is attributable to a number of unusual engineering elements: single overhead camshafts, rather than dual, reducing reciprocating mass and weight; three valves per cylinder (two intake, one exhaust), rather than four, enhancing catalytic converter light-off; two spark plugs per cylinder, capable of slightly staggered firing, to optimize combustion; one ignition coil per plug, to optimize the spark.

Its 90-degree V6 layout rather than the more common 60-degree design allows Mercedes to create V8s using the same basic tooling, which should lower the overall cost of producing a line of engines. The result is a family of advanced new engines that will be used throughout the Mercedes model line and will take the company well into the next century.

Mated to this powerful engine is a sophisticated 5-speed automatic transmission that uses computer magic to interpret your intentions and select the proper gear. That's the idea, anyway. In our driving we encountered a couple of situations--passing on narrow country roads--where we wanted maximum power right now. The computer seemed to think that this wasn't a good idea, and selected a gear that was one cog higher than what we had in mind, which left us out there in the oncoming lane a bit longer than we would have liked.

Some other noteworthy techno-wizardry:

Keyless ignition uses an infrared data transmitter that interfaces with the ignition system to start the car. The car's electronic ignition lock can still read the data in the key fob, even if the key fob transmitter is dead.

The computer that governs the antilock brake system (ABS) monitors your braking habits. It then senses when you're in an emergency braking situation, primarily on a basis of how quickly the brake pedal is depressed, and applies maximum hydraulic pressure to the brakes, up to and over the ABS threshold, even if you panic and ease pressure off the brakes. Mercedes claims that most of us don't apply maximum braking force in emergency situations, and that this system can reduce stopping distances by as much as 45 percent.

The CLK is equipped with front and side airbags for the front passengers. The front passenger seat uses a sensor that tells the airbag sensors whether it's occupied; if it's unoccupied, the passenger-side bags won't deploy, which can save a bundle in repairs.

Allied with this is the new Mercedes BabySmart system, which lets the airbag computer know when the passenger seat is occupied by a child restraint seat, thus deactivating the right front airbag. It requires the purchase of a specially designed seat from Mercedes to work.