... or even, what's the tuning procedure when using the air pump? Is the hope to tune the engine on the ground using the solenoid with the air pump reacting only to rpm changes and then in the air tune only the air pump? This would have the air pump handling all of the mixture corrections due to engine unloading while the solenoid handles changes due to air pressure and temperature changes only.

Is that workable? will we be able to achieve a set it and forget it type of operation? Will it be easier to tune? My gut tells me we should set the pump up to mimic the pressure curve we would get from muffler pressure and that attempting to modify that pressure profile will prove difficult but I haven't tried it yet.