Speedo Cal
 

Hey guys gotta question for ya;

I have a 2000 GT 5spd and have bought 3:73 gears and a speedo recalibrator from Ford. My question is does anybody know the percentage (plus or minus) of change putting the 3:73 gears in will make from the OE 3:27's ? I think I've worked it out to 12.5% slow so I have to increase the signal by 113% (there are no .5% settings) am I right ?

And yes I know I could just wait until the gears are in and get a buddy to drive beside me and compare but I want to do it all in one shot and be finished. Since this is such a common gear ratio I'm sure plenty of you have done it so let's hear it. :tup

Never mind I figured it out.