Opel’s upcoming 2011 Corsa ecoFlex model, powered by a 1.3-liter CDTI turbodiesel, boasts an impressive fuel economy rating of 53 miles per gallon (U.S.) and an equally noteworthy CO2 emissions of 98 grams per kilometer. Credit the 95-horsepower, 140-pound-foot engine; stop-start technology; and an optimized five-speed transmission with taller gearing for the ecoFLEX model’s fuel-sipping
