I can get the idle set correctly so it runs around 12.8-13.5 with 15" of vacuum but at 1500-2200 its still running 11- 12.5. Cruise rpms around 2900 are running 13.5ish.
from 1500 to 2200 its still on the "idle cicrcuit" but the pressure differential is higher. probly 16 to 18"Hg.
Cruising at 2900 is highway speeds - probably 60 mph ish in top gear. Pushing enough air the boosters (main circuit) is supplying most of the fueling.
How to lean out or shut down the "idle circuit" as the throttles open varies with the type of carb. But that's what has to be done. Might be able to get away with increasing just the idle air bleeds.