Speedo adjustment with 3.73s gears

[TopEndCobra]

my cobra is getting some 3.73 gears installed on today, and from what i understand the speedo might be off after they are in. I have an xcal 2, and wanted to know how much of an adjustment do i need to currect the speedo??
thanks for the help

 

[BADASS03SVT]

if your tuner allows you to make changes, you just plug it in, reload your tune and select "yes" for change parameters. under gear ratio you just pick 3.73s. super easy