It is not a carb issue. Before doing anything else, do the 5 min PCV test in post #41.
Yes, there may be other problems, but they will take more time to trouble shoot & may require special tools [ compression tester ] to check.
The low vacuum may well be 'normal' if the engine has had a bigger cam fitted. That will THEN require some fine tuning of the ign system & carb to make every thing work in unisyn.
