If it's got an original equipment Delco coil you need a resistor. With the engine running you need to see around 10.5 volts at the coil + terminal when the charging system voltage is 14+. If you're running on a 12V battery without the charging system in operation the voltage at the coil needs to be around 9V.
Jerry


"It is better to be silent and be thought a fool than to speak and eliminate all doubt!" - Abraham Lincoln
Cringe and wail in fear, Eloi- - - - -we Morlocks are on the hunt!
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