this is what i came up with before i aborted the project
i was going to use a low pressure wastegate of around 5# opening pressure and trim the opening point with a bleed valve, the other side labeled actuator i was going to use some sort of linear actuator (on the other side of a seesaw linkage), either pressure, vacuum or electric, the opposing not in action servo would act as the pivot for the acting servo to move the rack arm, tweak it to a nice starting position at rest and then tune the servos to move it to the desired end point
its not a perfect solution but it is the concept i came up with, i never got as far as prototype so it likely has bugs, the last actuator i came up with was electric and run by a stand alone controller that you can set the end points and have 3 different preset positions, it was about $150 and i had started thinking about running the whole thing via a single more advanced actuator/controller with more preset position capability and have the thing advance the rack as pressure sensors would be tripped by rising boost
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96 3500 5 speed drw C&C 11' flatbed, 887 215hp, turbonetics stage I ball bearing turbo, S&B intake, isspro boost/pre turbo pyro/fp gauges, 330 marine's, 10# plate a hair back of forward, 3k gsk, ats 3 piece exhaust manifold, kdp tab'd, timing at 16.5*, fluidamper and rip's mufflerless 4"
dualls