Those hoses coming out of the sec diaphram housing lid do not connect to the intake manifold.
They do not work like that. That is not boost referenced power valves.
Do not test like that. ALl the tubes re for is to equalize the sec opening rate between the front and back carb.
Its just a vac balance. They just connect together.
You cannot test at 14psi boost without boost referenced power valves. (unless you remove them and jet the carbs way up to compensate.) ( drag race only)
Consider yourself warned. Stop what you re doing . You car not ready to test #14psi with those jerry rigged carbs.