The formula is: "Effective Ratio" = "Old Tire Diameter" divided by "New Tire Diameter" times "Original Ratio". Note: These are actual heights of the tire NOT what it says on the sidewall. Example: A guy has a set of 28.2 tires and changes to a set of 32.8 inch tires and has a 4.11 rear end ratio. 28.2 divided by 32.8 times 4.11 = 3.53 effective ratio. Hope this helps.

Stranger
Frank in Iowa

1955 Second Series Chevrolet Shortbox NAPCO with a Rockwell Transfer Case
"Mater's Cousin"
In the Stovebolt Gallery
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