85 MPH to 140 MPH speedo

Discussion in 'Fox 5.0 Mustang Tech' started by TrophyHead, Dec 14, 2003.

  1. What is needed to get my speedo accurate to 140 MPH?

    I just got a 140 MPH guage kit. I dont want to do 80 and have it read 130. thanks
  2. u have to get it re-calibrated...and i think i heard that is $$$$$
  3. Any body know where I can get re-calibrated?

    I would guess a speed shop?
    Do you need a dyno?
  4. What year is your speedo? 86 and before style of 87-89 syle?

    Two Brothers performance in CA does it. About $70.00 plus shipping.
  5. It a 88...thanks 70 bucks not to shabby.
  6. If you have the gauge faces, then just get a 140MPH speedo from anu 89-93 Mustang. ALl you need is the actual speedo mechanism. You just swap it in. It's only two screws and then use your new gauge face overlays.
  7. Probably gonna be hard to find...I'll check Ebay. :nice:
  8. might be selling minwe with white faces :nice:

    butttt 5L5...my friend had an 87 and it came with a 140 speedo with white faces bu the cluster was from an 88 (says on the side) and it was like 40mph off...went and got a 85 speedo and it was all good again.

    and 88 ws definitely an 85 speedo year ALL year right? not a half/half job
  9. Yeah 87 and 88 had the 85MPH speedo...all year.
  10. so can you take a speedo from an 89-newer and bolt it in an 88 without recalibration??? was looking to do the same with my gf's car
  11. you'll have to trim the gauge faces depending on year... otherwise- YES. I did it with my 89 140mph speedo into my 93 :)
  12. 87 and 88's were all 85MPH. 89 was a half/half year
  13. Yes, the speedo bolts in perfectly. What you do is unbolt the speedo from the plastic frame it's two screws. This is for the 90-93 speedos as the 89 is a direct swap over

    I think i have a pic

    Obviously you pull the needle off. But the speedo mechanisms are 100% the same physically, just calibrated differently.

    For setting the needle, see the little tick mark under the 0MPH on the factory face? With the needle stop out, set the needle so it points to this at rest.

    The thing with this method is that you need a gauge face. Obviously anyone who finds a 89 speedo can directly swap the entire unit over, but if you put a 90-93 speedo in you'll need a face

    if you go with white face gauges or some overlays you are all set.

    Others can try to CAREFULLY peel the 90-93 face off and swap it over to the 87-89 plastic frame. Use a heat gun to get it soft and transfer it. You will need to trim but it should work.

    I got my speedo from a junkyard for $20, and paid $65 for my BBK gauge faces