Originally Posted by sjs0433
So I guess with the way you have it setup the gm solenoid does most of the regulating and its only under wot that the mbc really takes affect?
part throttle, solenoid duty is <100%, therefore it allows some pressure signal to traverse through it and reach the actuator where it opens the wastegate and limits boost.
full throttle, solenoid duty is 100%, and can be for all intents and purposes, ignored. the only pressure signal the actuator sees is that which passes through the MBC.
now, can you turn the MBC down so that it's wide open, all the time? sure. you just get actuator spring tension boost levels (aka "wastegate boost").
just think of the MBC as a simple max boost clamp that you can adjust independently of the EBC. it will never allow boost to go above whatever its set at. (of course boost is ALWAYS uncontrollable under actuator spring tension, regardless of method.)