A speedometer Mystery

[LockDoc]

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Could very well have a different ratio in the head. I don't know if this site will help you at all but there is a lot of information on it.

http://www.transmissioncenter.net/sp...n_______va.htm

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[TobyArnot]

Thanks Leon,
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That's a great site, but it looks like most of the differences are on the tranny end. I didn't change anything but the speedo head itself. The linked page for "speedometer calibration" addresses the "turns per mile" issue and there may well be a difference there. The old speedo was (I assume [?] - original '70 model) had a round high beam light opening and a white on black field. The replacement speedo (year unknown) has a rectangular high beam opening and a pale green on black field. I'm too sore from crawling around under the dash to pull it and look for any small numbers referenced on the calibration page.
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To top it all off, this morning as I was leaving the house for work in a light misting rain, the wipers aren't working, but that's another whole issue.
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I think I will call the number on the website later today and pick the guy's brain.
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Again, thanks for the assistance.

[cdowns]

sounds to me like you were guessin b4 and guessin now with not a real true fact of what is what or how fast u r really goin

me? i'd drop the truck off at a place that has speedo certification and i'd pay to have it calibrated accuratly

[LockDoc]

Originally Posted by TobyArnot

Thanks Leon,

wwaah:To top it all off, this morning as I was leaving the house for work in a light misting rain, the wipers aren't working, but that's another whole issue.

Again, thanks for the assistance.

Not a problem Toby.

As far as the wipers check this thread out when you start digging into that problem.

http://67-72chevytrucks.com/vboard/s...d.php?t=413551

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