Hi All,
My '70 Challenger had already been converted to the Orange Mopar Electronic Ignition when I got it. I want to buy a spare Ballast Resistor, but am wondering if I need to get a special one for Electronic Ignition or whether the stock oem one at the local parts place will work ("Standard" brand) ? I think whatever is oem = "points-based ignition", but I didn't know whether this is diff for electronic.

If so, does anyone know the part# or a good place to get a new ballast resistor for electronic ignition?

Thanks a lot!

What coil are you running now? Some coils use different ohm resistors.

This one looks like a generic stock one - the black cylinder.

Use a standard 2 prong ballast resistor. 1 ohm

Mopar part number P5206436

or any parts store ask for a 1972 dodge 2 prong.

Thanks a lot. I'm glad I checked first. The "oem stock" one - for a points ignition car - Anyone know what would happen if that was mistakenly used on an electronic ignition setup? And is there a way to test the resistor with a meter to see which rating it has? Just curious ..

Thanks!

In order; take all wires off of the item being checked (for resistance). Ohmmeter on "ohms". touch ohmmeter leads together & adj the meter if it has a "zero adjust" (old analog types). Touch leads to each end of the part. No problem mixing/matching ballasts between points/elec just if the ohms is too low for the coil used it'll burn it out eventually. I have an oe (points) 2 terminal ballast on a stock elec ign (measured @ 1.7 ohms)& works good but I am leaving power on the table using that high of ohms. The ballast listed for the chrome or orange boxes iirc is 1.25 ohms and the race one 2444641 (.25) ohms. using the one (run) side of a later 4 terminal ballast is listed at a nominal .5 ohms (one I checked has 1.4 ohms) and wiring both sides of it together in parallel gives 1.1 ohms which would be perfect. A decreasing ohms value resistor will give you a hotter spark/more power but at the expense of shorter coil life.

Thanks Robert for the great info on that!

I've noticed that ballast resistors don't appear to be polarized (no negative or positive sides). Does it make a difference if say you mount the resistor upside down and the opposite terminals were used? I've always been curious about that one.

Thanks again!

Check DINTY68RR here on Moparts...4 prong resistors NOS CHEAP!!!!!!!

Hey your welcome and correct they are not polarized