Tire Sizes

[Don C]

The attached spreadsheet is set up so that anyone can enter a tire size and get the approximate diameter, widths, and recommended rim width.  Axle ratios can also be entered and the engine RPM at 60mph is shown, based on the tire size. The engine RPM can also be entered to check speeds, based on axle ratios and tire sizes.  The second tab shows gear ratios of various Ford transmissions.

NOTE: Added a tab for wheel and tire clearance calculations  5/7/19, corrections on 12/8/2020 and added a table of axle widths.

Because changing tire diameters will affect speedometer accuracy you can find information and a speedometer gear calculator here:

https://www.7173mustangs.com/thread-speedometer-gears?pid=163384#pid163384

View attachment Tire Sizes-v6.xlsx

View attachment Tire Sizes-v6.xls

 

[Odmark]

Thank you guys for all the inputs! I have decided to go with the 3.50 gears, as long as the pinion was 28 splines. He was unsure and going to check today.

 

[Don C]

I added a tab to the spreadsheet (Clearances) that will make it easy to calculate the distances between the inside and outside edges of the rims and tires for measuring and estimating the clearances from springs, fenders, etc.

 

[AcesArneson]

I added a tab to the spreadsheet (Clearances) that will make it easy to calculate the distances between the inside and outside edges of the rims and tires for measuring and estimating the clearances from springs, fenders, etc.

Thanks for the spreadsheets I will use them on my 73 vert in the rebuild. Truly appreciate all of the knowledge on this forum.

 

[Don C]

Here is the updated link for the Speedometer Gears
https://7173mustangs.com/threads/speedometer-gears.15595/

 

[Don C]

Here are the latest versions of the spreadsheets, with some minor corrections and additions.