The C30 CDI AMG holds a special place in Mercedes-Benz history because it’s the first and only mass-produced AMG-badged model powered by a turbodiesel engine. Introduced in 2002, it was billed by AMG as the world’s first diesel-powered sports car. The claim wasn’t true, but it likely helped would-be buyers get used to the idea of seeing CDI and AMG emblems on the same trunk lid.
Offered as a coupe, a sedan and a station wagon, the C30 CDI AMG wore the same exterior add-ons as gasoline-powered AMG-tuned w203 C-Classes. These included front and rear spoilers, side skirts and 17-inch alloy wheels mounted on fat tires. The chassis and suspension modifications were carried over from the C32 AMG, meaning the C30 had a slightly stiff ride that was nonetheless comfortable enough to spend hours on the Autobahn.
Power for the C30 CDI AMG came from a five-cylinder 3.0-liter turbodiesel engine that was derived from the mill found under the hood of the non-AMG, Europe-only C270 CDI. To be deemed worthy of sitting in the engine bay of a car fitted with an AMG emblem, the straight-five underwent a long list of modifications and it ultimately shared very little with the engine it was based on.
Hand-built in Offenbach, Germany, by the same mechanic from start to finish, the oil-burner was tuned to deliver 231 horsepower at 3,800 rpm and 398 lb-ft. of torque from 2,000 to 2,500 rpm. Power was sent to the rear wheels via a five-speed automatic gearbox. In its fastest configuration, the C30 could reach 62 mph (100 km/h) from a stop in 6.8 seconds and go on to an electronically-limited top speed of 155 mph.
To put those figures into perspective, the gas-burning C32 AMG was used a 349-horsepower supercharged 3.2-liter V6 engine that allowed it to hit 62 from a stop in 4.9 seconds.
In 2002, when governments around Europe were still struggling to explain to people what a euro was, the C30 CDI AMG carried a base price of €49,590. The list of standard features was fairly slim but it included Electronic Stability Control (ESP), a feature that many period journalists agreed was a necessity rather than a luxury. Buyers who wanted creature comforts such as a CD changer, headlight washers and a leather-upholstered interior had to pay extra.
That made the C30 a very tough sell, especially when performance-minded buyers could skip the Mercedes-Benz showroom altogether and buy a V8-powered 344-horsepower Audi S4 for just €52,420. Too expensive, not powerful enough and not very well suited to the AMG image, all three variants of the C30 CDI AMG were phased out in 2004.
The idea of a turbodiesel-powered sports car wasn’t new at Mercedes-Benz. In the 1970s, many years before the company purchased AMG, engineers toyed around with the C111, an experimental two-seater with Gullwing-like doors that started life with a powerful Wankel rotary engine.
When it became evident that the Wankel would never comply with the ever-stricter emissions regulations in both Europe and the United States, Mercedes changed course and fitted the coupe with an evolution of the 3.0-liter five-cylinder OM617 engine that was found in the w116, the w123 and, later on, the w126, among other models. Miscellaneous modifications (including the addition of a Garrett turbocharger) bumped the oil-burner’s output to a healthy 230 horsepower.
Mercedes set a couple of speed and endurance records with the C111 III, but it eventually dropped the idea of a diesel-powered sports car altogether and focused on building gasoline-burning engines.