[JL8Jeff]

You should definitely be getting the best mpg around 75mph. With a 6 speed it might even be closer to 80. These engines are most efficient around 2000-2200 rpm's so the 1700 is too low. Never look at the computer estimate, always go off actual miles and the gallons of gas. If you have a non stock size tire for your car and did not correct the speedometer/odometer you need to take the difference into account as well. I log every mile and every gallon of gas ever put into any of my cars. That's the only way to see the real changes from 1 tank to another, weather changes, etc. I'm not surprised you're getting 30+ but you might be able to get a little more with a higher cruise speed. Keep your windows closed as well during those drives, it will make a difference.