I have the X3 tuner with 3 custom tunes from Doug @ Bamachips. When I got the tunes they were for 3.31 gears and now I have changed to 3.73. To change the gear ratio you have to go to the custom tunes and it asks if you want to change options. You select yes, then it gives the options for fuel, shift firmness, rpm limit, gear ratio, etc. All the options like fuel, shifts, show 0 and gives the option to + or minus. Is this changing the custom settings or the factory settings? So if I go into the 93 performance tune and change gear ratio to 3.73 the change the shift firmness +4 then is this changing Dougs settings +4?