[uneasyrider]

Here's an update. I went out today and got more accurate about the whole process and found I' getting 19-20mpg NOT 28mpg. I found that the point I filled my car to last time WASN'T all it could hould. This time I really made sure I got it topped off. I was also doing 70mph not 60-65mph but I don't think the higher speed was the major factor it was the 2gals of gas I found I could still cram in there. It will look like it's close to as full as it can get and couldn't hold more than a few cups more BUT it will take about two gallons more if you carfully fill it. The first time I filled up on that first run I must have been more careful than on the second fill. Not that 19 or 20 is horrible but it isn't 28-30. Ooops. At least that explains the error. It's a straight forward calc. but the data has to be correct.