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Author Topic: 2 prong ballast resistor for electronic ignition?  (Read 398 times)

Offline chadb

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2 prong ballast resistor for electronic ignition?
« on: December 11, 2016 - 04:31:15 pm »
Wondering which resistor to use for my 70 340 cuda with electronic ignition. Bought a new harness from Bill Evans for electronic ignition, but see that most systems use the 4 prong resistor, his harness only has 2 plugs for the resistor. Do I use the 4 prong resistor and only use 2 of the prongs, or can I use a 2 prong resistor made for standard ignitions?  Thanks, Chad




Offline 70chall440

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Re: 2 prong ballast resistor for electronic ignition?
« Reply #1 on: December 11, 2016 - 08:33:47 pm »
Use what the harness is set up for; 2 prong works fine.
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Offline Chryco Psycho

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Re: 2 prong ballast resistor for electronic ignition?
« Reply #2 on: December 11, 2016 - 11:08:40 pm »
Most ECUs now have only 4 pins so the resister is inside so alll you need is the 2 prong to drop voltage to the coil

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Offline burdar

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Re: 2 prong ballast resistor for electronic ignition?
« Reply #3 on: December 12, 2016 - 12:25:27 pm »
 :iagree:

4 pin ECU= 2 prong ballast
5 pin ECU= 4 prong ballast

Offline Aracer

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Re: 2 prong ballast resistor for electronic ignition?
« Reply #4 on: December 16, 2016 - 12:46:54 am »
You want the lowest (ohm) resistance for a stock or MP ECU coil/box. M.P. has a .25 ohm part with high current ability. Or the .5 ohm smaller ceramic MP part. Don't use the 1.2 ohm type, it will be hard to start.
      I know it will run with out a resistor, but you need to isolate the rest of the car from the ignition coil/box. If not the lights and radio may pulse with the plug firings. Get some spiral core resistance wires and plugs, to have radio reception.   
       They will run great with no resistor, solid wires and non-resistance plugs and never misfire, even though it's "wrong". but forget about sneaking around, it will electronically set off car alarms with it's radio noise. Frig up the track employee's headset and buzz TV sets as you pass by.