I don't know about carbs, however I do know that when I throw my throttle open by hand with the air cleaner off, my secondaries seem to never open, even under a very healthy rev. I can see there are vacuum houses and regulators and **** on the side, connected I think to the secondary's butterflys. Someone help me?

 

You will not see the secondaries open by winging the throttle open on a carb like a Qjet or even a holley vacuum sec carb. the air door hs a spring and vacuum delay diaphram to delay the opening responce so the car does not bog when you floor the gas pedal.
This responce delay is nessessary because the fuel flow response time is slower than the airflow response time. ( the fuel is heavyier, more inertia) If the secondary air door open to quick, like if you wing the throttle open, the car will bog.
If you want to see if the secondaries are working, wire them shut so they will not open and go for a test ride.
then remove the wire and try it. You'll feel and hear the difference. On a holley you disconnect the vacuum diaphram linkage. A holley picks up the vacuum signal from the right side venturii. There is a built in restriction inline that restricts the vacuum buildup in the secondary vacuum diahram housing that serves the same function as the qjets air door tension spring and vacuum delay break.

 

thanks

-Randel

 

Q-jets also have a secondary lock-out mechanism that prevents the secondary throttle plates from opening until the choke stat is fully open.

-Bob