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Canadian Poncho Homepage -> Canadian Poncho -> The Lounge -> Converting speedometers from mph to kmph
Post Info TOPIC: Converting speedometers from mph to kmph
65Camino


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Converting speedometers from mph to kmph
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Changing the El Caminos speedometer to read accurately in KM. Every formula I find is based on mph  

Ive got a 15 tooth grey drive gear. 3.31 rear axle. Tire is 205/60/15 with 842 revs and a diameter of 24.6.

 

Right now using my speedoo app on my phone actual speed is 55 while the showing 50 on the dash. 

Ive got an Orange 35 tooth driven gear. 



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seventy2plus2


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According to my calculations you need to reduce your speedometer cable by 10%, that means a driven gear of 38.5 teeth for a 2.56:1 ratio (presently a 2.33:1 ratio). Choose between a 38 or 39 tooth.



-- Edited by seventy2plus2 on Friday 4th of December 2020 12:12:43 PM

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Prefectca


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In the early eighties you could buy a speedometer adapter for the speedometer cable to convert to kilometres. Your Speedo needs to be reading correctly though.

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seventy2plus2


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Prefectca wrote:

In the early eighties you could buy a speedometer adapter for the speedometer cable to convert to kilometres. Your Speedo needs to be reading correctly though.

 I had one of those adapters new in box and sold it to a member here likely 10 years ago.



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unruhjonny


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I was just going to recommend an adapter line that!

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427carl


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65Camino wrote:

Changing the El Caminos speedometer to read accurately in KM. Every formula I find is based on mph  

Ive got a 15 tooth grey drive gear. 3.31 rear axle. Tire is 205/60/15 with 842 revs and a diameter of 24.6.

 

Right now using my speedoo app on my phone actual speed is 55 while the showing 50 on the dash. 

Ive got an Orange 35 tooth driven gear. 

      P205/60R-15 ?     really?   low rider ?      



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65Camino


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427carl wrote:

65Camino wrote:

Changing the El Caminos speedometer to read accurately in KM. Every formula I find is based on mph  

Ive got a 15 tooth grey drive gear. 3.31 rear axle. Tire is 205/60/15 with 842 revs and a diameter of 24.6.

      P205/60R-15 ?     really?   low rider ?      

 Nope, not really stock tire is 205/75/14 with a diameter of 26. So its only 3/4 lower. 

But nice to hear from you. 



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