Your gear should be a 4.57. With 30" tires, it puts 40 mph at about 2,000 rpm. There is no easy or cheap solution for a good gear ratio. You can get 4.10 gears with a pumpkin swap, Carter's website has a tech tip on this. Randy's ring & pinion sells 3.90 gears, but you have to swap out pumpkins, and spend big bucks for the gears. Swapping out the entire differential is another possibility, but they are 3.5 inches wider, causing more problems. I am looking into a differential swap with newer wheels, which have more setback, but it could take a while. I have a lot on my plate right now.
