RPM switch set to close the bypass at somewhere above 2200 rpm, and a pressure valve plumbed from the pressure side to bleed off excess pressure back to the inlet side of the intake? The extra pressure sensitive bypass may be needed at some point in the rpm range to stay below your chosen boost level.

Last edited by gregsdart; 01/27/17 10:41 PM.
8..603 156 mph best, 2905 lbs 549, indy 572-13, alky