resistor

[joshua dewitt]

i have converted to msd 6-tn and muti step retard unit on the car, but i left the factory icm box just upgraded to mopar orange, and a few mins, if msd craps, can drive home, now, i still have the 4 pin in the car, does it have to changed to a 2 pin unit? or can i just leave what i have, like i said just a back up. 1973 dart swinger. ???

 

[67Dart273]

You can leave it so long as you jumper the brown and "ignition run" or you will not have power in start. It's important to install as MSD instructs, IE run the "big red" power to a constant power such as the starter relay battery stud.

All your original ignition line is doing is acting as a relay trigger. The "small red."