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Hi guys, I currently own a 1957 Fairlane 500 4 door with a swapped 351 Cleveland in it and I know you early 70’s mustang guys have those in your mustangs, currently trying to get it to run after 2 years, swapped carburetor, solenoid, ignition coil, battery, wants to roll over but still no spark, the coil is connected from the solenoid to a resistor and then to the coil. Unsure if this is fine or not but resistor drops the volts down to 6, I feel as though that’s too low to get the coil to do it’s job, also head ballast resistors weren’t in fords originally. Please help
 

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In the factory set up, you should be getting 12 volts during cranking, then 6 while running. The resistor should only be in the circuit with the ignition switch in the run position. The purpose of this is to extend the life of the points and reduce heat in the coil.

Bypass the resistor and see if it runs like that. You will probably end up replacing points with an electronic module. That, and a modern coil will want 12 volts during run anyway.
 

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Lots going on here, does it have points?

If it does, check gap, check for corrosion, potentially replace

Check for voltage at the positive side of the coil with a test light during crank and key on (should be dimmer in the run position)

If you have power in run and crank at the coil, move the test light to the negative side and repeat, should flash as points open and close, if it doesn't then it's in the distributor

If you don't have power during crank, see if you have power on the I terminal of the solenoid during crank, and that the wire is hooked up to the solenoid. FYI - Power for the ignition during crank comes from the solenoid on a Ford, in the run position it comes through the ignition switch.
 

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Get a test light & see if you are getting voltage to the coil when cranking & with the ignition on.
If so check point gap.
If point gap is ok replace condenser.
Then ohm check the coils primary windings & then secondary.
You next option is install a DS11 distributor with a MSD module or a GM HEI module mounted on a heat sink. Get a coil with low primary resistance such as a MSD Blaster 2 or 3. Pertronix now makes a low primary resistance coil.
Or replace the points with a pertronix 1. But all of the above need a full 12V to the coil &r module.
Also run an ohm check on your coil to distributor secondary high tension wire.
 
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