I found this website talking about the differences in inductance between high and low impedance injectors:Test Injector Inductance
According to this guy's test, low impedance injectors have both a lower resistance AND lower impedance, not just lower resistance as compared to high impedance injectors. To me, this means there's less inductance capability in the coil to kick back. So the stock EEC with resistors should work just fine as long as there's enough current to get the injectors to open. From my preliminary tests using my injectors and an 8ohm in-line resistor, the injectors open just fine with as 12v source. But that was with no pressure on top of the injector.
In a normal gasoline injector, the pintle must raise while the fuel flow is down and into the intake manifold. The higher the pressure, the more effort that is required to lift the pintle. If the pressure rises too much, the pintle won't open as happens with some injectors like the Multecs. Although Fuel Injector Connection has a video showing a set of various injectors being run up to 140PSI!!!! The Multecs kick out just a tad over 60PSI, but the Bosch and some other brand (forget what they were right now) continued to inject right on up to 140.
In the case of my CNG injectors, the pressure is from below the injector. The gas flows from the rail, up towards the injector coil, then does a complete 180 and flows back down through the center and out a nipple that a rubber hose connects to.
Best I can figure is the hollow bar that the injector coil slides down onto has slots in its sides. The pintle in the center of the hollow bar blocks the slots off and seals the outlet. When the coil energizes, the pintle is raised allowing gas to flow from the rail, through the holes in the bar, and out the center. If that's how it works, there's no pressure on top of the pintle holding it down. The pressure is on the sides of the pintle. And thus the only resistance the coil is pulling against to raise the pintle is the spring that pushes the pintle down.
89 Ranger Supercab, 331 w/GT40p heads, ported Explorer lower, Crane Powermax 2020 cam, 1.6RRs, FMS Explorer (GT40p) headers, Slot Style MAF, aftermarket T5 'Z-Spec', 8.8" rear w/3.27s, Powertrax Locker, Innovate LC-1, GUFB, Moates QuarterHorse tuned using BE&EA