Have you adjusted the idle mixture screws for the highest idle on each one?
What do you have the ignition timing set at?
What torque converter stall speed do you have.
If you want to check for a vacuum leak, after trying to adjust idle mixture, slowly cover the carb air horn with a rag while engine is idling, if RPM goes up you have a lean mixture probably caused by a vacuum leak. You can make sure your brake booster isn't leaking by pinching the vacuum hose shut and monitoring RPM for a fluctuation.
Hope this helps.