O? I know it's possible, by using power items, to at least have two 31's, but how can I get 4? What I do at the moment, is just upgrading parents all the time (Right now, I have two Darumaku with both 2 31 IV's, and whenever I get a new third 31, I just replace the new guy with one of the previous parents to hopefully see that new 31 on more pokemon), but this doesn't guarantee me that I actually do get the additional 31s, other than the two 31s I get from using power items (and even that isn't guaranteed).
If I'm missing something, I'd love to know what to do better, because I really do want to work on getting better IV's.