Hot Rods Ballast resistor

Im running a 181 L4 mercruiser (Chevy) in my Model A. Running stock points distributor. Do I need to run a Ballast resistor?

 

yes or a coil with built in resister

 

It depends on your coil, as tb33 said, some coils have built in resistor and you connect to 12v direct. Older design coils you need the resistor.

 

You didn't say whether you were running 12v or 6v, makes a difference. As does the coil that you are running. Without that info, can't answer the question

 

its 12 volt

 

now all you need to know is the coil maker and part number

 

Yes, you need a ballist resistor or resistor wire...........

 

Maybe , maybe not as said earlier depends on the coil!!

 

I never quite understood why a resistor is even needed. Can anyone explain the basics? Why didn't they always just make coils so they don't need external resistors?

( OK, yes, I'm a dumb***. It's well known and I have accepted that a long time ago. So, let's skip that part of the discussion if possible. )