There are just so many things it could be. Where to start?
I guess a good a place as any, is to see what the boosters are doing,while the engine is idling. They should be dry.
Perhaps the idle speed has been run up, to compensate for late ig.timing,leaking floatvalves.leaking power valves, or too much fuel pressure.
Yeah I think those boosters will tell you something.
Some manifolds suffer from puddling. Sometimes through temperature problems. Sometimes through less than optimum design.
Perhaps your valve lash is on the tight side, or gets to be on the tight side after warming up.Big cams can send a compression pressure spike back up through an open intake valve.(Well they all do it to some extent). Well this spike, if it finds its way past the booster, can signal the carb to dump a bit of fuel. If all 8 cylinders do it, this can be a problem.
I have never had a hemi, nor tuned one. But I seem to remember those cross-rams having tuning issues,back in the day.
You need to dry up that intake, I think.And checking the boosters is where Id start.Well actually the float level is where Id start. Or maybe boosters first then float level. Naw just check the boosters first. If theyre dry,the float level will be at least close.
How about cluing us in as to timing numbers? Idle speed? Idle vacuum?Single plug heads? Timing controls? Velocity stacks?Engine temp?