speedometer

[Kenno]

Hi ,

I am running an escort mk1 lotus twincam - type-e rocket - atlas 3.9/1 - 13 " wheels .
Since the conversion the speedometer reads to high .
I ve read that the diff ratio from a standard escort 1300 also is 3.9/1 , would swap the speedometer from a 1300 car fix my problem ?
The speedometer i have now comes from a mexico
what else could i do to make the speedometer work better ?

[katana]

Change the speedo drive gears in the gearbox to suit the diff ratio - changing the instrument will make no difference!

[Forest_rallying]

I would think a MK3 Cortina speedo drive wouldn't be too far of.