I agree with Cheyenne. I think the LS1 even gets better gas mileage than the old V6/700R I had in it. As far as power is always there, even with the motor being stock and all. Combine the LS1 with a great drivetrain and you get one hell of a fast truck. I ran a 14.8 with 3.08 gears and a one wheel wonder, so that should tell you.