| Prior to hitting the target boost, is the wastegate solenoid totally open (ie, operating at 100% duty), so that no positive pressure goes to the wastegate actuators? Yes/no. The BC is keeping pressure from getting to the actuator during spoolup, however, the wastegate solenoid is a normally closed solenoid (when using internal, non-poppet style actuators), so the duty cycle is at zero%, not 100% during this phase. Or is it operating at whatever duty you have it set for, based on rpm and gear? On the AVCR, it uses rpm-based duty (the rpm-based psi value operates through this), so it will pulse the solenoid at the specified duty cycle based on RPM that appears in the settings->next screen (where it shows the graph of the duty vs. RPM).
The gear learning function, I believe, allows the AVCR to create a seperate duty vs. RPM table for each gear since the boost reponse of the turbo changes as load on the engine changes. This is where the controller gets into its "fuzzy logic" though, and it has been problematic on the vehicles that I have tuned. Also, is the boost linearly related to the duty cycle? Not really. Simplified, it is exponential, but there are several factors involved that make it a higher order equation, if you will, and it varies from one vehicle setup to the next. As an aside, the rpm based self learning curve that adjusts duty for a preset boost level is very cool, esp. with the large wastegate flappers on the sport 530s and no exhaust restrictions... they hold a solid 17 psi to redline, because the avc-r bumps up the duty a few percent past 5500 rpm to put some more tension back into the wastegate actuator sping. Yes, when everything works like it is supposed to, it can be a wonderful thing. :)
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