Re: Converting Speedo from Mph to Kmh?

Posted by Dave Kenney On 2009/1/14 14:22:10

I use a GPS in my Packard. I bought a 6 volt (+) ground to 12 volt (-) ground converter and wired it into the cigar lighter which I would never use anyway for it's intended purpose. I plug the GPS into the lighter socket and stick the suction cup mount on the speedo glass. The cable speedo is out by about 5% with the slighly smaller tire diameters I have on the car. The GPS is accurate and can be switched to MPH or KPH as well as giving other information. The speedo on my Canadian cars are in KPH and I travel in the USA quite a bit but like Owen stated conversion is pretty simple anyway and I have never had a problem.