MSD "Ready to Run" distributor

The MSD ready to run operates on the same inductive principle as the stock mopar electronic ignition. Even if you are using an MSD Blaster coil you still need the ballast. Use the MSD recomended ballast.

It's only when you use the capacitive discharge type system (i.e., MSD 6A, 7A, etc) that you can eliminate the ballast resistor.