Curt- the bifilar coil from the original post at the top of this thread is a passive device meant to resonate using the radiant energy of the earth’s magnetic field and whatever energy is present from the interaction of the fuel passing through the line. I presume that if the liquid fuel is in resonance, it will be easier for injectors to atomize, and engine vacuum to vaporize. Initially, if I’m correct, injector pulse durations will be long, so it would take some time for the computer to trim back.
Your setup was different in that you were inducing a strong magnetic field and cooking the fuel passing through your vessel. You didn’t say it outright, but it sounds like at or around the 4 mile mark with that setup, you vapour locked the engine; by bypassing your inductive fuel cooker, the liquid gasoline allowed the engine to function as designed once again.
Thinking about Curt's design, the welding rods increased the surface area of the fuel passing through the vessel AND made a nice core for the electromagnetic forces to saturate , and by wrapping the entire thing with the alternator wire, he was processing a whole whackload of vapour - liquid fuel didn't have a chance. from there it went straight through the carb's float bowl and jets into the engine. it seems some control on the supply side would've mitigated the problem - a valve to control fuel supply to the vessel he constructed, possibly vacuum regulated, perhaps?