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tire sizes for factory 8 inch rims?
I want to get larger tires in the rear than in the front. 

What is the largest tire I can fit on a factory 8" rim in the rear that will stay under the fender lip?
What is the largest tire I can fit on a factory 8" rim in the front that won't rub?

What brand would you recommend for raised white letters and where would you recommend I buy them?

1972 Mach 1 351 cj 4speed
"We confide in our strength, without boasting of it; we respect that of others, without fearing it."--Thomas Jefferson

First - to help you out on the 'right foot';  There are no 8 inch factory wheel for our cars.  The largest would be the 15x7's (measured bead to bead - not outside lip to lip).

Now many buy aftermarket Magnums or other wheels and they are available many different sizes.  Your only constraints there are proper and safe fitment.

There are many threads already on here about tires and wheels for our cars.  And may will post up what they are running.


1971 Boss 351  
1972 Q code 4 speed convertible 
1971 Mustang Sportsroof  351-2V FMX 
1973 Mach 1 (parts car)
You can go here and download a spreadsheet that will give you information on how to measure wheels and the see what the effects of different sizes will have on your car.

When you are trying to maximize the tire and wheel widths, the backspacing of the wheel is critical. There have been many threads posted on the forum about what other members have found that work. Just go to the upper right of this page, click on search and search for tire size or wheel size and you'll get a lot of hits.

Backspacing rule of thumb on our cars are backspaces of 1/2 the rim width plus 1/2". In other words, a 7" wide wheel would use a backspacing of 4" and an 8" wide wheel would use a backspacing of 4-1/2".

“If you can't explain it simply, you don't understand it well enough.”
--Albert Einstein
You can also have your stock steel wheels widened and a custom offset/backspace, or sometimes even a larger rim diameter if you want. Wheel Vintiques use to do that. Probably still do. Really wasn't that expensive, either. Plus they can paint or powdercoat, not sure about chroming.
245/60R15 is very close in size to the F60-15s your car came with.


A 255/60R15 will fit fine on the factory 7" wide rim if you want a larger size in the rear. I've run 255s on the front with no issues.

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