Hei conversion troubleshooting

Do a voltage drop test on the 12 volt power to the HEI and see if the voltage is falling off when the rpm comes up. I forgot the voltage range that most factory replacement modules have, but a quick search at standard ignition parts should have it for your module. It could also be a rotor/reluctor phasing issue. But going by symptoms alone, my first instinct is that is what a bad HEI module acts like. Know anyone with a Suntune machine?