Welcome to the site.

Which distributor are you running?  The pre '57 Load-O-Matic distributors are problematic when trying to use them with three deuces.  What carbs?  The Holley 94's incorporate both venturi and ported vacuum at the distributor port and need to be modified to use a later model distributor if using the vacuum advance chamber.  What is the jetting in all three carbs?  Do the end carbs have power valves?  If not then larger jetting is required where the power valves have been removed.