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Old 11-21-2013   #4
WVZR-1
 
Join Date: Oct 2004
Posts: 1,884
Default Re: Speedometer calibration

Quote:
Originally Posted by Pumpman View Post
I will mark the DS and roll the tires to check the gear ratio.
I don't know that this would make it any easier to calculate but if we changed the tire rotation to minutes you should see your "mark" every 14.6+ minutes or just less than every 90* rotation of the tire for the 4.10 ratio, if the original 3.45 were present every 17.3 minutes or 104* rotation of the tire. There's possibilities maybe of 3.73 every 16 minutes or 90*+ and a 3.91 which would be 15.3 minutes or 90* + very little. There's of course 4.33's or 4.56 possible but very unlikely.

Really large numerical ratios or medium duty trucks this has helped in the past. It's been a long time.

For this you could just place a piece of tape or a paint mark on the pinion flange deflector that would be easily visible. Most every build should have the sheet-metal deflector BUT not all.

Last edited by WVZR-1; 11-21-2013 at 07:55 AM.
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