blitzing against slide protection

we've found the best thing to do is overload a side; generally we try to get 4 vs 3 on the weak side.
we try to get pressure off both edges and get the 2 vs 1 one match-up on the end man, be it a te, ot or rb. we've also had some success with running 2 through the same gap; not necessarily sound vs the run, but in an obvious passing situation it has given us some good results.
hope this helps.