63 Speedometer problem
Thread Starter
Instructor
Joined: Feb 2012
Posts: 108
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From: Helena MT
63 Speedometer problem
Hoping someone can suggest where to look for correcting a speedometer which is reading approximately twice the speed the car is going? The transmission is a 4 speed Muncie.
Last edited by Montana Mike; Mar 9, 2012 at 09:41 AM.
Thread Starter
Instructor
Joined: Feb 2012
Posts: 108
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From: Helena MT
It's no double talk when I say the car is really racking up the miles! I will check the adjustment on the speedometer. No work has been done on the dash cluster or transmission that I am aware of, however the car is fairly new to me.
Race Director
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C2 of the Year Finalist - Modified 2020
Is this the first time you noticed it? If so, the wrong speedo gear may have been put in the trans. The correct gear is determined by which trans and rear gear you have. 
Dennis
Dennis
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Instructor
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From: Helena MT
Team Owner
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From: Washington Michigan
6th Gear
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Did the car come from Canada? When Canada went metric (in the early eighties as I recall) some FLAPS sold adaptors that increased the speedo cable RPMs by 1.6 so the speedo would register KPH instead of MPH.
These units usually mounted right behind the speedo head. Check and see.
Mait
These units usually mounted right behind the speedo head. Check and see.
Mait
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Le Mans Master
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From: NJ Hockey beer league
It's virtually impossible for a speedo to read twice car speed due to a wrong speedo driven gear; there isn't anywhere near that range of difference in tooth count in the available gears. You have a calibration issue in the speedo head itself - it needs to come out and be checked out/rebuilt by one of the speedo restorers.
Most likely the adjustment spring has sprung. 
Thread Starter
Instructor
Joined: Feb 2012
Posts: 108
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From: Helena MT
Pulled the instruent cluster and there is only the cable going into the back of the speedo. So appears you guys are right....must be inside of the speedometer. Thanks all for your help.
