GAS MILEAGE ....

If its a typical A-body 15 gal. tank you better plan on 170 miles maximum. Many 340s only get 10 mpg or so in "city" driving. But, if it's mostly highway, with 2.76 gears, you can plan on going somewhat further. But not knowing the exact type of driving you are doing or the actual size of the tank makes this an impossible thing to predict with any degree of accuracy.