Speedometer/odometer '51 Car

[Motorhead6]

I have a '51 Victoria in which I have changed the speedometer gear so that it reads correctly according to two different GPS's. My problem is that the odometer is about 10% slow. While going down the Interstate, when the odometer indicates I have traveled 20 miles, both of the GPS's indicate I have traveled about 22 miles.

Does anyone know how to fox this short of changing out the entire speedometer. I don't really want to lose the original low miles reading of the current odometer.

 

[ford3]

unfortunately that is an internal gearing problem form the speedo to the odometer, with out taking the speedo apart and changing the gears there is no way to fix it, if you have another speedo that works, use it, its easy to reset the milage on the new speedo

 

[Frank Miller]

I think you need to go back to the original gear so the odometer reads correctly. Then have the speedometer calibrated. I am not sure how accurate these were new. I personally like the GPS for reading speed.