The Love of the Ballast Resistor

PrestonUSA1

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Hello FCBO,

So my local parts place does not have the single circuit ballast resistor that came stock on my 68 300, what is the Ohm rating for the original? What is the specification for the Ohm range? I am planning on using one out of the pile of my 70s ballast resistors that have 2 circuits if they meet spec.

Best Regards,

Preston
 
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i always thought that all mopars came with two spare sets in the glove box
 
This is a common part and any local store should have one.

It may be called different things like Coil Resistor, it is the same thing!

Autozone
Duralast/Ballast Resistor
Part Number: AL795
Alternate Part Number: AR-17

NAPA
Ignition Coil Resistor
Part Number: ECH ICR12
Product Line: Echlin Ignition Parts

O'Reily
ACDelco - Ignition Coil Ballast Resistor
Part # C1101

BWD - Ignition Coil Resistor
Part # RU19
Line: BWD

BWD - Coil Resistor
Part # RU12
Line: BWD

Use the right part
 
In answer to the question... the resistance should be .5 to .6 ohms.
 
The dual ballast resistor has a .5 ohm resistor that goes to the coil (same value as point ignition) when the ignition switch is in "run" position and a 5 ohm resistor that limits voltage to the ECU.

So.. yea, it's not the "correct" ballast appearance wise, but if you hook up to the correct .5 ohm side, it will work just fine.

At 2:00 AM on I-80, bypassing the resistor altogether will be a little tough on the coil at lower RPM, but chances are it will get you to the next exit.
 
The dual ballast resistor has a .5 ohm resistor that goes to the coil (same value as point ignition) when the ignition switch is in "run" position and a 5 ohm resistor that limits voltage to the ECU.

So.. yea, it's not the "correct" ballast appearance wise, but if you hook up to the correct .5 ohm side, it will work just fine.

At 2:00 AM on I-80, bypassing the resistor altogether will be a little tough on the coil at lower RPM, but chances are it will get you to the next exit.

A foil gum wrapper... oh wait they don't make those anymore, a paperclip...

Only one side of the dual is correct, I don't recall what the other side is but yes it will get you home. and do we know which side is which?

But if you are getting one for the glove box then get the correct one.


Alan
 
A foil gum wrapper... oh wait they don't make those anymore, a paperclip...

Only one side of the dual is correct, I don't recall what the other side is but yes it will get you home. and do we know which side is which?

But if you are getting one for the glove box then get the correct one.


Alan

There's a notch that orients the plug. Just have to figure out where the notch is relative to the .5 ohm resistor.

It's been a while since I had one in my hand, but if the back is open so you can see the resistor, the one with the thicker wire would be the one with less resistance.

Yea... Having a the right one for a spare is the best way, no doubt.
 
Of course.... If you are on the side of the road and you have a test light (something you should carry in the glove box too), you could check the resistor with the battery and the test light. The side that lights the tester brighter is the lower resistance (.5 ohm) side.
 
But if you are getting one for the glove box then get the correct one.
Alan
But that's only thinking for yourself. If your correct one is a two prong and your best Mopar buddy in the world travelling with you breaks down and uses a 4 prong....
 
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