Sniper EFI and ignition type

JRapley said

Well, I got it all buttoned up tonight. I initially switched the ignition all back to stock and had issues getting power across the ballast resistor. Dunno why, but it would have power on the hot side for both pins, but only power on the opposite side on one pin. So coil wasn’t getting power in start or run. Which was strange because the resistor ohmed out fine on the meter.

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Good decision because Sniper + ballast resistor = bad.

Holley specifically states in the instructions that the ECU needs 12V in both crank and run which basically renders the ballast resistor useless. To do that though, you must “tie the IGN1 and IGN 2 circuits together” somewhere behind the switch so it acts as one switch position that receives a constant 12v.

In the OE format when the engine is off and you turn the key to start, there is no voltage to the run circuit. When cranking the coil gets “full fielded” to aid startup. Once the car starts, you release the key back to run and there is no voltage in the start position because the alternator is providing the juice to keep it running.

Originally, the ballast resistor’s main function was to limit voltage to the coil in run or you’d burn up the points in short order. Not sure why it was kept that way when they went to electronic ignitions in the ‘70s but that’s a different thread.

Either way, the Holley stuff is designed to have the full 12v in both crank and run. That’s why it’s best to use the Hyperspark ignition components because while the ECU may “work” with other ignition pieces it wont be optimal.