When you hit the gas, there's an extra pump in the carb which will squirt fuel into the carb as the throttle is opened. It's what caused your vapors when moving the throttle when it would die after extended idling.
@RustyRatRod is right too, the trans should probably be downshifting at that speed when you mash it. That goes back to your kickdown adjustment...
Edelbrock carbs are notorious for being tough to tune the WOT bog out of, but many don't have an issue. Float level, pump shot, fuel pressure can all have an effect. But don't change more than one thing at a time and start with the accel pump since it won't affect everything else like the rest of the adjustments will.
Also, I'm sure better carb tuners than me will chime in - listen to them, I gave up on my avs and went to EFI because I'm a quitter LOL.
