I've got a 1995 Cavalier LS convertible with a 2.3L Quad4 and the best gas mileage I have recorded has been Imperial 42 m.p.g. , that was no jackrabbit starts and nothing over 80 kph (50 mph) and the convertible top was up and the windows were closed and this was all highway driving and there was a tailwind of about 20 mph. Tire pressure was 35 psi. Is this average gas mileage or worse or better than you get? I do know that when I drive around town the mileage drops way down but I was quite impressed when I checked the mileage on that one trip and came up with that figure.
Let me know what your gas mileage is please. Please state U.S. or Imperial (Canadian) miles per gallon
Vic