Occlusion Culling still not running smooth...

I really just want to keep my question simple and right to the point. Occlusion culling is culling the areas in my level map, but its still running really slow. I have tried so many variations to try and figure out what is wrong, but I've had no luck. Here are my current settings:

View Cell Size: .01 Near Clip Plane: .001 Far Clip Plane: 40000 Bake Quality: Production

What could I still be doing wrong? Why is my scene not speeding up? What are the best settings to guarantee things will speed up?