This report deals with different engine systems and the results of supercharged passenger car Diesel engines. Changes in the power characteristic of the engine by using a positive displacement charger, a pressure wave charger, and an exhaust gas driven turbocharger with variable area turbine nozzles are demonstrated. The different charging systems and their effect on brake specific fuel consumption are discussed. Furthermore, a comparison is made between the test results of the standard turbocharged Diesel engine of a passenger car and those of the same baseline engine equipped with a variable area turbine nozzles (VATN) turbocharger, both fitted to an engine dynamometer and to the car. A considerable gain in engine rated power, fuel economy, and torque at low engine speeds was obtained with the VATN version resulting in a much improved driveability.