I have and Edelbrock 1406 600 cfm carb relatively new on my car. It seems that the secondaries only open up if im at part throttle cruise and the put the gas to the floor. If I put it to the floor from a stop they wont open or sometimes they kick in when im like halfway through second gear. I know if the choke is activated they shouldnt open but this is when my car is fully warmed up and been running for a while. The screw that sets the idle on a cold start is all the way out to keep the idle at like 1000 in the morning when i first start up i dont know if that has anything to do with it. Thanks for any help.

 

It's supposed to do that. It has an air valve somewhat like a Q-Jet to keep the driver from making the car bog by opening all 4 barrels when the engine isn't flowing enough air (too low RPM) to need the secondaries.

If you want a manual secondary carb, get a Holley or a Demon.

 

You can remove some weight from the secondary air valve to make them activate quicker if you'd like,
or you could just remove the air valve completely.
Many times removing the air valve will cause a bog, but sometimes not.
Also, many times that bog can be tuned out by adjusting accelerator pump delivery, metering rod springs, ignition advance, or just eliminated by using a performance torque converter.

If you have a very mild camshaft with a dual plane intake, you may not get a bog at all by removing the air valve, and you might enjoy much better throttle response from your carburetor.