Speedometer Question

Interior

  1. 67 GTX

    67 GTX Well-Known Member

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    My 67 gtx came with a 150mph speedometer. The belvedere's came with the same speedo, but a 120mph instead.

    What I am trying to figure out is if there is any physical difference between the 120 and 150 speedos. The magnets and the cups for each seem to be the same size.

    I tested both with a constant speed electric drill, and they seemed to read about the same speed.

    From what I can gather, these should interswap?
     
  2. SDCoronet

    SDCoronet Well-Known Member

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    Just my 2 cents based on what I have read over the years:

    I believe that they will swap just fine. I also believe that the only real difference between the 120/150 mph speedos is that the internals are magnetized differently.

    Let us know how it works and post lots of pics!
     
  3. 67 GTX

    67 GTX Well-Known Member

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    I found out that they do swap, as the only difference is the different magnetization and slightly different hair spring.

    I'm having a 120 that I have (in better shape) converted from the internals of my 150 (rusted).