[OrrieG]

4.10 might be a little steep unless you get tall tires. My 74 axles are 3.74 with auto trans. There are rpm calculators online that let you play with the variables; tranny ratio output (1.0 in this case), rearend ratio, tire height and rpm. you can input any three to find the 4th variable. Salt flat racers also add in frontage area, drag coefficient to determine horsepower to get certain speed. Not a big deal for the trucks, but been playing with it for my Chevelle make over.