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hotrodder 11-08-2014 09:28 PM

speedo help
 
I changed the transmission in my '67 from a column shift 3 speed to a 350 turbo. the speedo is 10 mph fast, when changing the gear in the trans bullitt to get it more accurate should I go with less teeth on the gear or more? I believe the colors make the difference ?

hugger6933 11-08-2014 09:40 PM

Re: speedo help
 
You need to know the tire height and the rear gear ratio. Then there is a table on the web, maybe one on here as much stuff that is here wouldn't be shocked,it will tell you the tooth count needed for correct speedo reading [and color] for the drive gear[output shaft] and driven gear[speedo "bullet" some call it ] it is the cable end that into the trans. Now it is possible if the gears are close, you can change just the driven gear and not the drive to obtain proper tooth count. That would be the best hope that way you don't have to remove the driveshaft and rear tail shaft housing.

LockDoc 11-08-2014 09:41 PM

Re: speedo help
 
Quote:

Originally Posted by hotrodder (Post 6908662)
I changed the transmission in my '67 from a column shift 3 speed to a 350 turbo. the speedo is 10 mph fast, when changing the gear in the trans bullitt to get it more accurate should I go with less teeth on the gear or more? I believe the colors make the difference ?


Go to this site and scroll down just a little ways. There is a chart that you can use to figure out what you need. There is a lot of good info there....

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

LockDoc


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