The reason your secondary did not open all the way is that is all the motor wants. Secondary will only open what the motor needs. If you use a 780 CFM carb and the motor can only pull 700 CFM, the secondary will only open so much.
BTW: I do not have check ball in dual quad vacuum secondary Holley tunnel ram setup and does not bog at all. The tires spin so fast it practically put a hole on the black top, and it has 15" of vacuum at idle.
Last edited by lg1969; 03-26-2013 at 05:05 PM.