carb issues

Are you saying it there is a miss as you accelerate from 1/4 or 1/2 throttle?
or
Are you saying at steady speed and rpm it misses between 1/4 and 3/4 throttle?

When the primary jets are too small, my experience has been that the engine surge and try to die while driving steady. Depending on gearing this will occur somewhere between 60-70 mph.

A rich circuit will result in a lazy carb until super rich (ie choke on after warmup) and it will then noticibly loose power.

Idle circuit also feeds the 'transistion slot', so it supplies most of the fuel under highway speeds. Its also the circuit that needs the accelerator pump. Once the carb is fully on the mains, the boosters respond qucikly to throttle changes and the pump shot usually is not needed.

To seperate things out, test at steady low speed like 30 mph as well as from high speed, like 65 mph. See how it responds both to slow increases in throttle as well as quick ones.
I also agree with the suggestions above, especially to disconnect the secondaries. It does sound like an ignition miss, but nothing else is pointing that way. However dirt, poor drilling, or gasket is can be another reason it misses. Is this a 4150 4777 dash something?