if i want to get a lot of mph out of my jato, what is the most radical gear setup i coukld go to?
and is it the bigger the ratio the more mph or the bigger the ratio the more acceleration?

Problem is you need a motor to be able to push some high gearing to get more MPH. The 3.3 will push some revo 20 cb, 40 or 38 spur, but you should run some light weight tires and try and shave some weight on the truck to reach its potential with revo gearing. The jato as some very flexable gearing options. Buggy tires and wheels work better for the revo gearing set up. The buggy stuff is light weight and smaller in width so less rotating mass = more MPH. You need 17mm adaptors to run the buggy wheels.