I'm hashing out some ideas with a programmer friend of mine. My initial model uses a pressure sensor, a servo, and speed controller. They are relatively inexpensive black boxes from radio control vehicles. The turbo blades would default open by spring tension, but with the ignition key on close until XXPSI is reached, then open as wide as possible while maintaining XXPSI. One advantage is if anything electrical fails the spring should overpower the servo.

I still trying to think of a mechanical system that does the same.
Oh, and high boost with low throttle position shouldn't be a problem. You ever lifted out of the throttle going up a hill? There you go.

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I suggest we solve high gas prices with environmentalists... unfortunately they don't burn well.
1982 300CD, 220K miles: This vacuum system will be the death of me yet! (OBK #26)
1977 F150 400 C6 2wd, 10.2 sec 1/8 mile with 2.75 gears.
1965 Mustang. Mostly stock... LOL!
2001 Ram 2500, cummins, 5spd, 202k miles.(girlfriends)