Widest tire on 8 3/4 rearend - 1972 Dodge Dart Swinger

Hello all,

I rarely post on here, but I took this project car with my dad and there is a lot to learn about these older cars for me.

This is my 1972 Dodge Dart Swinger which originally had a 225 Slant 6, but since has been swapped with a SB LA 318 motor. Apparently my particular car came with a 8 3/4 rear-end! I am not entirely sure why, but I won't complain ha.

Now I am wondering if anyone has the knowledge of what is the widest rear-tires I can fit on my stock 14in rims, 5x4, and 8 3/4 rear-end?

Thank you!

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I have 255/60 r15's on the rear of my 70 Dart, with 8.75 rear n small bolts...

But I had relocated the spring perches in a bit, and also had 5 1/8 backspaced steel wheels made, so it is centered nicely. I can actually fit 275/60 r15's now if I want...

The fronts are 215/65 r 15's to fit well up front turning-wise...