sorry but there ain't a simple # answer, it depends on wheel width, tire diameter & width, and leaf spring/steering component clearance.
YJ's came factory with more backspacing than most other common wheels, factory or aftermarket. (i'm not sure exactly but i think the 15 x 7" wheels have about 5" of backspacing) Now most aftermarket 15 x 8"(or 10") have 4" of backspacing, this is why you see so many YJ with aftermarket wheels/tires that stick out past the fender flares.
now you can buy(or build) wheels with custom backspacing but you must be careful, if they have to much backspacing the will contact the tierods, or hit the brake drums/rotors before the lug nuts actually seat the wheel. also when turning, the tire will rub on the leaf springs.
and also the less backspacing you have put more stress on the balljoints, wheel bearings etc..(it kind of adds some extra unwanted leverage)
so anyway i would look at some other YJ's noteing the size (tire & wheels) and asking if they rub while truning. my expereince with YJ's is a 15 x 8" rim with a 30" to 33" tire is a good size, and on a 15 x 10" rim 33" to 35" tire is good, (both 8 & 10" wheels having standard 4" of backspacing)
also i've used 15 x 7" (and have them for sale) wheels with 35" tires and i guar0wnTee they will rub when turning.
so my preferance is that the overall tire diameter needs to be decided before choosing the wheel. after the diameter is decided i get the wheel with the most backspacing possible without causing problems (touching anything). now other folks will say "wider is better" but not me.
sorry about the long post, i just got to typing/wwwthreads_images/icons/smile.gif
3/4tonYJ
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