It is truly sad that all we will get in 2008 is a gas burner, rated for "40+mpg", and will require premium fuel. I currently get 47.14 mpg avg. with an ECHO, which is 1.5L and weights 2,060 lbs. You would think that a 1,700 lb car with 1.0L could do so much better?
Antoine, sending a pic of your car and mine. Just to show the idea. The black areas on yours are what I am suggesting to cover to test. You can see how I covered mine. Blocking the air going underneath the car lessened the negative pressures at the rear.