I've had centrifugal superchargers on cars. The boost is NOT steady at all, it varies directly with RPM. As RPM doubles, so does boost.

For example, if it makes 11psi at 6k, it will onlt be 5.5 at 3k. The blow off valve shown is way too small, it needs at leat a 1.5-2" throat to handle the volume of air that thing can move.

All that said, its not a bad price for what you're getting, but its going to be a science project to fit it up.

John C.