[Wgesnerjr]

Not sure on Chevy Quadrajets, I only have experience with Pontiac ones. But, the secondaries are not "controlled" by the choke, but locked out by the choke. Once engine is warm and choke is off, secondaries are unlocked.

I have found there is a small lock out that can be "bent" out of the way. But why someone would you want to use the back barrels before the engine is warmed up sounds foolish to me.

Also, if it is an electric choke, there is a vacuum pot called "choke pull off" that can go bad and the choke will not turn off. Again, not sure if Chevys use it but it caused all kinds of hell when it went bad on my Catalina.