What's the absolute maximum range of your Duster?

@cruiser What year is the car and does it have any lightened factory parts? Please tell use the about the engine, trans, rear gear and tire size. Any mods done to the engine/car etc....

What carb is on top?
What ignition system is being used?

There is a lot of ground to cover here and you have given us no clues to go on.
225 slant six engine, stock A-904 tranny, 2.76 rear end, stock one barrel Holley carb, stock ignition and coil, timed to 10 degrees BTC. Very stock and original.