One question I have is how did you get the alternator pulley to fit on the input shaft of the supercharger? It won’t just bolt on, The bore of the alternator pulley is larger than the shaft, not by much, but it is enough to cause problems. There is not a keyway in the alt. pulley, so the key has to be removed, or a keyway needs to be cut into the pulley (there isn’t enough meat to really add a keyway). The thickness of the mounting flange on the alt pulley isn’t thick enough and if the alt pulley is put onto the shaft the nut won’t hold the pulley be itself. There will be about ½” between the back side of the nut and the face of the alt pulley, making it super sloppy.
I really find it hard to believe that you (or your friend) made 15# of boost with a blower pulley that small. A lot of people have a hard time with a 10% pulley slipping much less one with one half the surface area, and not even a press fit. So how did you do it?
Jeff