How many MPG are you getting on your cars and what are your setups. Thought it would be nice for all of us to share some common info.

What gas mileage can I expect from a 79 Caprice 4 door with an inline 250. My plans were to turbocharge that baby, I had all the info, but not the money and still dont. What would be the best mods to increase gas mileage and get a bit more power as well. Right now I am getting 10 MPG tops and the car feels really sluggish. I know its a really heavy car, but what would you consider to be the best gas mileage I could get out of it?