AJ/FormS said

Generally; The rim width should be plus or minus 1 inch of 70% of the section width, or equal to the tread width. So .70 x 325/25.4 = 9 inch;the manufacturer thus thinks you could mount that 325 on a rim of 8 to 10 inches.But,since the tread on a 325 is closer to 10, and since it would be really difficult to find a 15 x 9; then 15 x 10 it should be, cuz 8 inches would not work very well for most applications, and certainly not for you.
Since the section width of a 325 converts to; 325/25.4 = 12.8inches when mounted on the 70% rim(9inch), this section width will grow a tad when mounted on the 10 incher, perhaps a qtr inch per side, making your 12.8 section equal to about 13.3inches, or an actual 338mm section.
Clear as mud, right?

I have found that a 325 on a 10 inch rim is fine for the dragstrip and fine for most driving situations, but in reality the tire pressure has to be pretty low so that the tread wears evenly, like 20 to 24 psi. Well that don't corner worth beans. My 295s are barely supported on a 10 incher; requiring 24 psi for long tread life. And it don't corner all that well at 24, but it's acceptable for an old fart like me who is slowing down.So,
it is my opinion that if I was to run my 325s full time, I would want a rim wider than 10 inches, so I could drive a little harder around the corners, without the rearend doing it's little squiggely dance.But my stock wheelwells would not accept that, as the section width would grow enough to put the sidewalls into the tub walls on a more or less continuous basis.
With minitubs, Ima thinking 12 inch rims would work for me.And the deep dish wheels would look great.
But for you,I also suppose that the rear end would need to for sure be narrowed with 12s and the springs would need to be moved into the rails for sure.Even with a custom offset wheel, which,even though I like the look of deep-dish wheels, I would still forgo,by using a large backspace wheel in an effort to put the cornering force towards the outside of the wheel, and maybe put less twisting stress on the studs. I'm no engineer but it makes sense in my little head.
And that takes you back to post #2..............

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