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speedometer question on an older car need help thanx

2K views 9 replies 7 participants last post by  107485 
#1 ·
im using this calculator to figure out what gear i will need on the speedo cable does any one know on a 67 xr7 how many times the cable has to spin before it registers 1 mile the calculator used examples such as 940,960,1000 x's it is suposidly stamped on the speedo but wanted to order the gear soon before i have to take my car apart btw here the link so the rest of u can figure it out as well!
http://www.bgsoflex.com/speedo1.html

i jus pulled my cluster out of the car yesterday and where should this stamp be? looks like i will have to take it apart unless any of u know off the top of ur head thanx again!
 
#2 ·
Why are you messing with the speedometer cluster? Any meaningful changes, that a consumer can make, are available either by changing the driven gear, at the end of the cable...the end near the transmission tailshaft. The other change that is worth making is pulling off the tailshaft and changing the drive gear.

Opening up the speedometer cluster to adjust mile/revloution is similar to opening up a watch case to reset the time. There is more than enough adjustment in the drive and driven gear to make the kind of changes for anything other than certified speedometers.

If you need that much percision, take it or send it off to a professional Speedometer shop. Other wise, just change the driven gear...the gears are color coded which tells you which pairing will give the "truest" reading based on rear gear. If you need more percision, you can also measure the wheel/tire to make it more exact, then work that variable into the formula (most formulas assume a 26 in tire wheel).

As indicated in the "readme" text on the site...use 1000 rpm for Fords....meaning rev/mile in this case.

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<font size=-1>[ This Message was edited by: Beoweolf on 3/28/06 1:37am ]</font>

<font size=-1>[ This Message was edited by: Beoweolf on 3/28/06 3:26am ]</font>
 
#5 ·
LOL thanx! does anyone have an idea? or know of a locla speedo shop in their area i could call to get the info from them?
 
#6 ·
Not to hijack the thread, but how many of you have a "local speedo shop" around? I always see this mentioned in magazines, but have yet to find that elusive "local speedo shop" in my town of close to 80,000. In fact, the closest shop I can find is over 100 miles away in a city of 4 million. I guess living in "flyover country" has it's disadvantages.
 
#7 ·
yeah this is really odd cause out of all the boards im on no one seems to know but once i find out ill be sure to post itr up!
 
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