Cobrajeff is on the right track.
You need to increase your air correctors to 190-210. If you run out of accelleration at the upper end, then go to a smaller air corrector. The mains may be a bit too large also. I run a stroked 427 with 48 IDAs and 37mm throats and my engine seems to like the mains about 150-155 with the 210 air correctors.
You idle circuit also seems too rich. I would suggest a 110 holder with maybe a 55 jet. The idle screws should be out about 3/4 turn.
While most people use the F7 tubes, they all also seem to complain about the 2700-3000 rpm stumble issues. Try the F5 tubes. They change the point of the emulsion start and they made my system run very smoothly through this area. There has been some discussion that even F2 or F11 tubes will work very well for the street.
Be sure that they are synchronized very well also. It will account for some of the roughness or stumbles as well. Also, what by-pass valve are you running in the bottom of the fuel bowl? 50-55 bypass valves also seem to work well for most people. If you have the zero valves installed then you will run too rich on accelleration blasts. (Lots of black smoke).
If you want to talk more about this in person, send me an email and we can exchange numbers. I am very glad to help. Good Luck.
