thank you. Started playing with it tonight. Appreciate the help

 

got my speedo calibrated with the 4.45 trans. entered gear ratio of 4.45 then adjusted vss in increments of 100 till I hot 72000- Then fine tuned to a final 72050. Pretty much right on with GPS

SO if you have a 4.45 trans with 225/40/18 wheels- it should RATIO- 4.45 VSS-72050

if it is reading to fast still adjust the VSS UP more in increments of 100. IF you are reading slow adjust down. Pretty simple!

 

Good info!

 

I went from 3.82 to 4.45 and I'm only off 2 mph per gps, and may have been there before the swap. Not real sure why.

 

If you're changing the final drive ratio in a fwd car, nothing needs to be changed within the tune what so ever. Not even the final drive settings.

If you're changing tire sizes though, all be it not absolutely necessary, you can adjust some of the vss settings to get your speedo a little closer to exact. In most case though, people tend to go wider more so than taller or shorter so changes are generally not needed. If they do go taller/shorter, it's usually pretty minimal.