In Europe, where diesels are as common as good coffee, Mercedes' E-class is available with five diesel engines ranging from a 2.0-liter four-cylinder to a 4.0-liter V-8 in the E400 CDI. The top-of-the-line V-8 boasts twin-turbochargers and direct injection, making it the most powerful diesel V-8 in a passenger car. Unfortunately, like marzipan the big diesel will remain a treat that only Europeans will enjoy.
If your last diesel experience involved the General Motors 5.7-liter diesel from the early eighties you will probably not believe the E400 CDI burned anything but gasoline. The engine starts quickly, idles quietly, and doesn't leave a cloud of acrid smoke behind you. Under acceleration the only sound that intrudes is the whistle of the twin-turbos forcing air into the engine. Turbo-lag is non-existent as 413 lb-ft of neck straining torque is on tap from 1700 to 2600 rpm. To put that into perspective, the diesel matches the torque of the infamously powerful Audi RS-6. Horsepower is not as impressive at 256, but it is enough to propel the E-class to sixty miles per hour in 6.7 seconds on its way to a 155 mph top speed. Fuel economy is respectable at 25.0 mpg in the European cycle, which beats the less powerful E320's 23.8 mpg.
Twenty years ago, as gasoline prices dropped Mercedes diesels began retreating from our shores.... Read full article