Single or dual ballast resistor?

[64SF]

Am converting my 67 Satellite 440 to electronic ignition. Have new distributor, orange box and a electronic voltage regulator, dual field alternator. In looking at different wiring diagrams and reading different articles I've seen single and dual ballast resistors used. Which one should I use in my application? Thanks.

 

[Mopars & Missiles]

Single, 0.5 ohm.

 

[2059]

depends on which dist./set up you use . I had to use a dual for my set up as that's the way the harness was fabbed for the Mopar Electronic ignition.

 

[Bee383]

on my 383 elec ign orange box,i have a new m&h harness set up for dual ballast and dual field alt.just did the mad electric ammeter bypass - everything working great.happy i went that direction so far.

 

[Nacho-RT74]

4 pins ecu, single ballast. ( dual can be used thought using the correct wiring disposition )


5 pins ecu, dual ballast.

 

[mobileparts]

The crazy thing is the "book" always said that for points ignition -- uses the 2 prong resistor;
and that for electronic ignition -- uses the 4 prong resistor.
Hence, for 1970 & earlier + 1971 w/ points -- use the "RU 11" - 2 prong resistor;
for 1972 & later + 1971 w/ electronic -- use the "RU 12" - 4 prong resistor.....
Do you know how many MILLLLLLLIONS of cars that are out there are that have converted to Electronic over the last 40 years
still have the 2 - prong resistor and are still functioning 100 % properly... Take that, "book". anybody care to comment?!?!?!

 

[68 Sport Satellite]

Mopar chrome ECU box here - running single 2-prong ballast, 1-ohm. No problems. I thought I heard the single was the better way to go....

 

[Nacho-RT74]

Ok... let's clear up

dual ballast provides two sources by two diff resistances. One is 5 ohms ( secondary ) which feeds the stock 5 pins ECU, and the other one is anything between 1.5 or .5 ohms ( Primary ) which feeds the coil.

single ballast just provides power for the coil. Resistance varies depending on which one and application, between 1.5 and .25 ohms

on 5 pins ECU, the 5th pin takes ONE POWER SOURCE from the secondary ballast resistor on dual piece.

on 4 pins ECU, the secondary resistor is not anymore outside, was moved to INSIDE the ECU... that's why the pin is gone

you can fit a 4 pins ECU on an stock 5 pins system without problem, simply the secondary resistance power will be going to, ANYWHERE... the pin is not there

you should NOT use the 5 pins ECU, on a system set to 4 pins. Probably your car will start up and ride around, what doesn't mean will work propperlly

better now ?

If you ask me WHY ? I have not the certain answer about, but my thoughts are the secondary resistance ( inside or outside ) senses voltage variations and temp, to modify the dwell, spark and whatever value of the ignition system