1974 Brain Box saves the day.

George Jets said

Here is the factory 4 pin ballast resistor with the 5 pin mopar style brain box as set up originally.

I bought this truck from the original owners, all original so I know it had not been changed.

Is this the proper setup for 1976, 4 pin ballast resistor with 5 pin Brain Box?

The top of that 4 pin ballast resistor gets hot and the bottom of it stays cool. Guess that is the way it is supposed to work creating resistance so it goes easier on the coil while running.

View attachment 1715623675
This is the way it was wired when I bought it and had the 5 pin '76 brain box on it.

Click to expand...

Here is another 4 post ballast resistor running with the 5 pin brain box on the "Run Panel" for the engine run stand.

It runs the engines fine. Does this layout look correct, resistor coil or not . . etc ?



Have always been under the impression that the 5 pin brain boxes use the 4 post ballast resistors.

Thinking that you can use a 4 pin brain box on a 5 pin harness plug, (but not the 5 pin brain box on the 4 pin harness plug . . don't know here) but then do you need to switch to a 2 post ballast resistor, or just keep using the 4 post ballast and all is fine ??