depends on the car.. Some people bolt 315's on and never rub. Others have to roll the lip on the wells, beat a couple spots in with a hammer, and buy an adjustable Panhard bar to center the rearend perfectly.
I have 315's and they were rubbing until I adjusted the Panhard bar and already rolled the lips because they would cut the tire on the 15" wheels with DR's I was running at one point. After I Uber slammed the car I just had to adjust the Panhard bar.
Ohh.. forgot one thing. the Bump stops stick out into the barrel of the 11" rims so if you let the axle drop they will catch on the rims. Jack the car up under the rearend to keep the suspension compressed or else you will scratch the inside of the rims on the bumpstops.