As you know @RAMM boost is only a measure of restriction to flow. The combo you tested was likely too efficient to make use of an entry level supercharger like a torque storm.
Making 540hp/560tI wouldn't use too efficient I would use big port , high flow, low port speed resulting in lower than expected boost--I figured 3-4 psi max. As I understand it the customer had TQstorm machine the crank pulley a custom size to spin the supercharger at max speeds knowing it is undersized to begin with. J.Rob