Holley/Demon Carb stumble

Here’s my current thinking.......

The reason you had no flow with the ball valve set for 9psi is....... it was(most likely) closed.
If you cracked it open at all, I can’t understand how there would be no flow.
The “concern” I have is, the flow went from 50 seconds at 6psi to 115 seconds at 8psi.

Pressure flows from high to low, so I understand there’s going to need to be some pressure differential at the ball valve to get flow.

The test with the lower pressure is just to see if the system will provide adequate flow and maintain system pressure with something less than a 2psi pressure drop.

Before doing the test with the regulator set for 6.5......
While it’s still set at 9psi, I’d try adjusting the ball valve up from 6psi a 1/2lb at a time, just to see about how much pressure the system, as currently set, will maintain while pumping a gallon in about 85 seconds.
We know 6psi is in the low 50’s, 8psi is almost 2mins....... is 7psi close to 85 seconds?

The reason I’m focused on this is, I’ve never seen the symptoms your experiencing have anything to do with the carb calibration.
If it was carb/fuel related......it was a supply problem........ in as much as the bowls weren’t staying full enough.

The odd thing about it is....... it didn’t seem to do this when those bowls were on the Demon body, right?