Hi Guys
Richmond Gears has a calculator on there web site for guys like us trying to figure out what gears would suit our needs the best. You just have to punch in your HP, Tire Size and RPM you want to go threw the lights with and it spits out the gears you would need, or dam close to it anyways.

www.richmondgear.com

I used there web site to buy the gears i needed and it worked out great for me.