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I did not see a reference to that 1-way valve in the URL's previously posted. Can you provide one?
I can see a one way valve being used to suck the air out of the wastegate to close it. But I can see a vacuum applied to the wastegate damaging its diaphragm, as it was no designed for negative pressures. Also, while at idle, it would draw air from the MBC valve's bleed orifice and that would create a vacuum leak which could affect idle speed. but maybe not. It also would affect the mixture with T7's with air mass meters, but this may be too small to matter. The amount of vacuum at idle that the diaphragm would see would depend on the ratio of the pressure drops across the orifice and the check valve. It looks like a MBC in reverse.
Personally I expect that by the time boost starts to run back up again, the wastegate will be closed, and the orifice will be discharging the pressure until the boost cracks open the ball-spring valve. The real world gains may be limited to folks are shifting very agressively.
As for other strange ideas, I do have my share, I was thinking that the bleeder valve orifice could be a relief valve. This would require the use of the check valve to get the air out. Then the wastegate could open faster once the ball-spring opened. This would help control overshoots. This would however make the vacuum on the diaphragm worse. So now we would have three valves. What a mess. It could be created in one block, perhaps in lexan or another durable clear plastic. The details are obvious, but the the ball spring seats would have to be pressed in using hard metal. Cut-in plastic seats would not be stable with the heat and the balls could then stick in their seats. This deserves some serious sketching and beer! If it was done, it would help with overshoots and might allow a manifold pressure tap to be controlable in cold weather. Probably will get stuck in the fantasy stage with other big ideas in the mental junk yard!
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