A lot of times one of the ways of dealing with belt slip is to get a larger pulley for the idler pulley. This pulls the belt around more of the blower pulley. How close can you get the belt going up one side of the blower pulley to the belt going down the pulley? Basically how much flex is there in the belt as it move and how far away from itself does it need to be to avoid hitting itself and getting destroyed?

 

Or if you move the idler closer to the blower. The closer you are to the blower pulley the less deflection in the belts, especially the return portion of the belt. I think the answer is to look at some of the OEM supercharger systems. Looking at some of those and they wrap the snot out of those things. I always try to see what the manufactures do because despite what some may think they have a lot more info than we do.

 

If you have proper tension with a good tensioner it shouldnt deflect more than a quarter inch at most and thats only when you shift and it change speed really fast.