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The "original" benefit of an external resistor on a coil was to allow for the resistor to be bypassed during starting, to get better voltage to the coil.Thanks for clarification. So I should be good with either coils. Anything else to look out for in the aftermarket world when ordering? Or just a good quality coil should be good to go?
The "original" benefit of an external resistor on a coil was to allow for the resistor to be bypassed during starting, to get better voltage to the coil.
The starter draws a lot of current when energized, and battery voltage can drop by a volt or two. lower voltage into the external resistor means even lower voltage to the coil, resulting in a weaker spark.
My 1973 FJ40 with external resistor has a built in circuit that provides voltage during starting to the coil directly, bypassing the resistor, resulting a hotter spark. When the ignition key returns to the "run" position, the bypassing stops, and normal voltage is supplied to the resistor.
The mavens of FJ40 technology suggest the benefit of the bypass circuit is only of real benefit in very cold weather, where battery output is compromised by the effects of the cold on the battery's electrolyte. I suppose it could help with run downbatteries as well.
I have no idea if your model has the bypass feature, which is found on older, non gear reduction starters, with a wire coming off the starter solenoid.