I was able to put 31" tires on my stock 92'. I have no rubbing at all in turns. This is because I have after market offset rims with less backspacing. (Lemme know if you dont know what that means, I didnt at first either)stock backspacing is 4.5" I have 3.75". The only rubbing I have is on the rear fender flares, and its only under heavy flex or a bad bump, not too bad and livable. I defiently recommend getting offset rims, because thats what really makes the tires look bigger. I saw someone with 31" on stock rims and it didnt look any bigger. You want them to stick out mroe to give it a wider look.
Currently: '14 JKU
Past vehicles: '92 YJ, '97 TJ, '10 JK