speedo gear drive

[bluejohn]

hi all. i am changing my diff from 3.9 to a 3.54 in my anglia, do i need to change the speedo drive in the gearbox if so which one do i need i understand they are colour coded so which one do i go for. many thanks john

[Vista]

Yes it will affect your speedo reading, how much by I couldn't say. Nor can I tell you if there's a different speedo drive that will correct the error.

 

You can remove your speedo and send it away for calibration (see link) but I think most people just learn to live with it

 

http://www.speedycables.com/calibration.html

[rallyesport04]

i used to change my diff regular to find a happy medium all i used to do is put the sat nav in the window to get an idea of actual speed an speedo speed at 30 upto 70 an went from there

[bluejohn]

thanks anyway. i did the gps thing 3,000 revs equals 50 mph.got my new diff now, putting it in weekend and we will see