I have the Indigo E/I and after running it for around 10 years without a resistor, I called Tom for an opinion. He asked me to try a resistor on mine to see if I could detect any "cold starting or while running issues". The E/I hot feed is on the resisted side with the coil. I never did check the voltage, I just installed the resistor supplied to me. I have been using it for a bit over a year now and did not notice that I had made any changes at all. The E/I will work will with lowered voltages, as long as you stay within suggested voltages. I absolutely did not notice anything
and I must say it did suprise me a bit
.
Dave Neptune