For the first time ever, two of the world’s top car engines are electric motors, on the Chevrolet Volt plug-in hybrid and on the all-electric Nissan Leaf. They’re on the 2011 edition of Ward’s 10 Best Engines, awarded annually to the most technically advanced automotive powerplants. As proof of how rapidly car propulsion technology changes: Only two of the engines are carryovers from the 2010 winners, two are heavily modified repeaters, and six are new. Trend to Turbocharging, Supercharging If there’s a trend, it’s toward turbocharging or its cousin, supercharging. It’s on five of the eight combustion engines. With turbocharging, exhaust gases spin an impeller that forces more air and fuel into the engine; supercharging uses a belt-driven impeller. Many automakers believe turbocharging offers the highest efficiency gains – the same or more power with less fuel consumption than a larger engine. 2011 Ward’s 10 Best Engines (Test Car) 3.0-liter TFSI Supercharged DOHC V-6 (Audi S4) – repeat winner3.0-liter N55 Turbocharged DOHC I-6 (BMW 335i) 1.6-liter Turbocharged DOHC I-4 (Mini Cooper S)3.6-liter Pentastar DOHC V-6 (Dodge Avenger)5.0-liter DOHC V-8 (Ford Mustang GT)1.4-liter DOHC I-4/111kW Drive Motor (Chevrolet Volt)5.0-liter Tau DOHC V-8 (Hyundai Genesis)80kW AC Synchronous Electric Motor (Nissan Leaf)2.0-liter DOHC I-4 Turbodiesel (Volkswagen Jetta TDI) – repeat winner3.0-liter Turbocharged DOHC I-6 (Volvo S60)Geek-to-English translation: I-4 = inline four, I-6-inline six, TFSI= turbo fuel stratified injection, N55 and Tau = BMW, Hyundai codenames, DOHC = double-overhead camshaft. “Engine” generally means a compression engine; “motor” generally means an electric motor when used technically but an engine may be loosely described as a motor. Breakdown of the WinnersFour are six-cylinder engines; two each are four-cylinder, eight-cylinder, and electric. Three are from the U.S., three from Germany, and one each is from Britain, Japan, Korea, and Sweden. The countries are where that automaker flies its corporate or divisional hat but some are regional or global efforts: Mini is British and is owned by BMW of Germany, with the engine manufactured in France as part of a BMW consortium with PSA Peugeot Citroen; Mini’s previouis previous engine came from Brazil. Two hybrid winners in 2010 didn’t make the 2011 list: The Ford inline-four-cylinder Duratec 25 hybrid engine and the Toyota inline-four Hybrid Synergy Drive engine. For the full story on the 17th annual awards, see WardsAuto.com. To be eligible, the engine had to be new, heavily modified, or a winner the previous year, and had to be in a car available the first quarter of 2011.