RÜSSELSHEIM, Germany — Opel, General Motors' European subsidiary, has unveiled the first vehicles to wear its environmentally conscious Ecoflex nameplate: the 2009 Astra and Corsa.The Astra, which is available as a three-door, five-door or station wagon, will feature a 1.7-liter turbodiesel engine that makes 110 horsepower and 192 pound-feet of torque. The impressive part is that it will only emit 119 grams per kilometer of CO2 while getting more than 52 mpg. Opel achieves this by making the axle ratio longer, optimizing the engine management system and lowering the engine idle speed.The Corsa manages even better numbers by emitting only 109 g/km of CO2 and getting 57 mpg. Power for the 1.3-liter CDTI engine is limited to 75 hp and 125 lb-ft of torque. A lower ride height, smaller tires and reduction in weight all help the vehicle make this jump in efficiency.These two models will be available before the end of 2008, and Opel has plans to introduce the Ecoflex variant of its new Insignia model in the summer of 2009.What this means to you: These models show that there are simple ways to better fuel economy without using alternative fuels. — Mike Lysaght, Correspondent