The best way to find out how much your truck weighs is to take it to some scales and have it weighed. The weight of your truck can vary with different motors, options, how much fuel it hold etc...I had a 84 F150 4x4 with a short box and it weighed right around 5200 pounds with a 1/4 tank of gas, this might give you a ballpark figure. If you want the acceleration like one of those cars you seen today, you need torque and some low gears like 4.11.