[Mike C]

It sounds like once the carb transitions off the idle and primary circuit that it clears up. I too would be looking at jetting up and 4 sizes seems to be a good start.

Before that, try adding two full turns on the mixture screws to richen up the idle mixture and see if that doesn’t improve things.

I assume that all of these issues are at a steady throttle application and not when you are “punching it”? Sudden application of throttle and response issues are usually because of insufficient accelerator pump shot. But Edelbrocks are not as affected usually because of the secondary air door that keeps from giving too much air that the accelerator pump can’t make up for it.

Great looking truck BTW.