Too lean jetting will make it bog, but don't jet up till the bog quits, it may then be too rich. If acceleator pump squirt isn't enough, it can bog even if jetting is fat. Adjusting one of the cicuits to eliminate bog will make that circuit too fat.
First, make fairly sure your jetting is right. Also check float level, too low will make it lean and bog.
Next adjust the pump linkage. Remove all play between springed bolt and pump lever, if any, but not so that linkage bottoms out. With carb at full throttle, you should be able to push the pump lever another .050 or so.
Next try different cam positions, as D.I. mentioned. Pump cams have 2, some have 3, adjustment holes. There are also different pump cams. What this does is to adjust how aggressive the pump lever moves. Each cam or adj hole change will require the linkage to be readjusted. This is time consuming, but try as many possible as you can before going to the next step.
If bog is still there, then go to a larger squirt nozzle. You want to use the smallest you can, that why you need to try pump cam and positions first. Don't over tighten the screw when changing or you can throw the carb away. Your 390 probably has an .025. Go up one size at a time. Sizes are .028, .031, .035, .037, .040, .042, .045, .047, .050, .052.
If you have spare nozzles and pin drills, drill some larger and mark them so you know what they are. Once you get as big as .045, you'll need to use the hollow screw, or drill your own. I had a #3310 750 cfm vac sec on a big block Mopar motor that needed a .055, yes bigger than whats available, I had to drill it myself. Same carb on a different big block Mopar only needed a .042. Carbs need to be tuned to the motor combination, very seldom are they perfect out of the box.
Fine carb tuning takes patience, because once you get one circuit correct, you need to go back and check the other circuits because all will have a small effect on each other.
Circuits to tune;
idle
transfer slot - not adjustable
jetting
power valve
accelerator pump
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