VW already has a 2.0-liter diesel engine that delivers 236 hp and 368 lb-ft of torque, which it debuted in the Passat sold outside the U.S. By adding a variable valve timing system, further optimizing the gas exchange cycles and installing an electrically-driven turbocharger, engineers have managed to boost power to the aforementioned 268 hp.
The electrically-driven turbocharger is the same design previewed by fellow Volkswagen Group brand Audi. An electric motor is used to spin the turbocharger’s compressor at zero to low revs, with high-pressure exhaust gasses taking over at higher revs. Volvo has also shown a concept engine featuring this technology and many other automakers are working on their own versions.
Volkswagen DSG dual-clutch transmission
Further savings can be brought about by a coasting function VW plans for its future drivetrains. Described as a next-generation engine stop-start system, the new coasting function deactivates an engine at low speeds (i.e. below 5 mph) or during high-speeds when the driver takes his or her foot off the accelerator. When required again, VW says the engine is restarted quickly and “extremely” comfortably.
These technologies are part of VW’s continuous efforts to reduce the average fuel consumption and emissions of its vehicles 25 percent compared to 2010 levels by the year 2018.