i would like to know how to correct for tire size with my U7170 or at least change the gear ratio to make up for the larger tires??
Phil Preader 530-933-9276 or [email protected], thank you

i have a 99 ford powerstroke and a predator U7170 and i want to recalibrate my speedo for the larger tires, i have noticed in the gear ratio section its asking me for a BASE NOV? what is that and what do i put in there? is there a divider or something i have to use? any help is nice as thats the ...