I would put an old/another cap cut so you can check rotor phasing.
It sounds like your spark may be jumping around in the cap when the mechanical advances due to the rotor moving too far away from the terminals it should be firing to.
Check out my video on this:
Awesome. I’m gonna run with Occam’s Razor here and say that I bet my distro phasing is off because I probably misaligned it a bit when I installed it. I know with the slot that you can only be in or 180 out, but with this EFI kit I was supposed to be at 12 degrees BTDC on compression stroke of cylinder 1 when dropping it in in order to line up the Hall effect sensor a certain way. Gonna bet that I probably got the stroke wrong.
