I am building my wire harness after swapping a 305 of a 6cyl. The starter motor has a post for a ballast resistor. My old engine didn't have this.

Can someone tell me if I need to wire this up, why and how? Another two weeks and I'll be ready to fire it up!

Thanks,

Steve

 

Only if you are using a coil that requires a ballast resistor; you don't state what Ign you are running

Some coils run at a lower voltage (say 9V) and get 12V from the starter terminal direct to the coil bypassing the ballast ( which drops the voltage down ) when cranking only to boost the startup spark.
If the 9V coil had 12V on it full time it would burn out

 

Wow. I had not thought of that. I have an HEI dizzy. I installed a power center from Painless. Its directions say to run a wire from the panel directly to the HEI battery terminal. I have not measured the voltage there, I just assumed it was switched 12v.

So what should be the correct voltage at for an HEI dizzy?