I know how turbo's work, and I am a little familiar with the jackson racing supercharger. but the vortech units confuse me. the jackson racing sc gets 8psi at like 1500rpm and holds it till redline. but the max psi is 8, maybe 10 with the upgrade kit. but the vortech units offer a trim on the compressor that is with in the center island of efficiency ( on a compressor map) and put out up to 30psi. does this mean that since it is belt driven it gets full boost at the 1500 or 2000 rpms or does it start low and build to 30psi depending on rpms? also this would mean that if 5krpms meant 20psi then you wouldn't need wot like on a turbo cause the sc is rpm dependant where the turbo is load/throttle position and rpm dependant. am I on the right track or way off in left field?

please shed some light or a link to more info ( I have already read their website)

thanks