You could do much better if you slow down, the best optimum speed for mpg is 45 mph, with the stock gearing, it should be at 1600 rpm and on level ground should get 27 to 30 mpg...
you can get up to 90 mpg on a downgrade, so learn to hypermile..
Hypermiling :: Maximum Miles Per Gallon http://www.hypermiling.com/car-mpg.html
Check it out... Hypermiling will increase MPG for any car - you save money by buying gas less often.
should get 27 mpg on the highway if its a manual. invest in an aluminum driveshaft ($260) and underdrive pulleys ($100) and you should see another 2-3 mpg.
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