Q: i dont no what kind of v8 it is but all i no is that it has one ,
A: It can vary hugely, without knowing anything about the engine. Worst case, 454 big block, carb, not running right, and lots of drivetrain loss, 4-5mpg best case, 327 small block, fuel injection, aired up tires, non dragging brakes, 15-22mpg