[Barnsnake]

2000-2500 rpm is not my idea of idling.
Do you mean stationary in neutral? Carbureted hotrod engines generally have some ragged metering transitions without a load on them.
Do you feel the same thing under load when moving?

If you have a fairly radical cam it probably won't run right with the timing as retarded as you indicate.

A little more info on your cam, intake, carburetor, compression ratio, and timing curve would be helpful in providing useful suggestions.