Rear end gearing tech question

Think about optimizing your setup based on torque curve. If you are going to dyno the motor, see where the torque really starts to climb and plug in your tire size and different gear ratios until you find the one that puts you at cruise(70mph) just into your particular torque curve. Example: If your combo don't start making power until 2500, don't be cruising at 1800. If you are not going to dyno, then at least you can use the cam manufactures rpm spread. Wallace racing .com has easy to use calculaters to help figure.