Power to Coil
Thread Starter
Burning Brakes
Joined: Jul 2004
Posts: 783
Likes: 38
From: Mankato Mn
Power to Coil
68 Small Block. I've converted to Pertonix ignition & coil ! I had a ballast resistor that I eliminated. I have what I assume is a resistor wire that went to the coil. Can I use it ? If not, where can I get 12 volts from. I've read posts that said to take it from the wiper motor. Where does that resistor wire go ? I don't want to rip the harness open to find out but I can't find it inside of the car !!!
Instructor
Joined: Oct 2021
Posts: 157
Likes: 29
From: Montezuma Ga
I would use the old 12v power that was going to the ballast. How about just connecting the 2 wires at the ballast (deleting it) and use that power? I think its what you are asking..... Bottom line, key on, 12 volts........
2026 Loser of the Year
Joined: Sep 2013
Posts: 36,597
Likes: 7,046
From: New Or-leens Loo-z-anna
My resistor wire went to the fuse block on the firewall on the driver side.
If Petronix requires a full 12 volts you can also run a new wire from the i terior fuse block.
There is a extra terminal IGN.....Connect a 12 qage insulated wire to your new coil and run the wire along the harness into the interior and attach it ti the spare IGN terminal.
The coil should receive 12 volts only when the key is in the ON position and also in the crank position.
Usually members apply shrinkwrap to the end of the resistor wire that unbolted from the original coil...then they tuck the resistor wire away on the firewall where it cant be seen.
I think there is also an original 2nd wire that comes from the starter solenoid and attached to the original coil........the 2nd wire will not be needed with the Peyronix (I think).
Other members feel free to correct my info if necessary
If Petronix requires a full 12 volts you can also run a new wire from the i terior fuse block.
There is a extra terminal IGN.....Connect a 12 qage insulated wire to your new coil and run the wire along the harness into the interior and attach it ti the spare IGN terminal.
The coil should receive 12 volts only when the key is in the ON position and also in the crank position.
Usually members apply shrinkwrap to the end of the resistor wire that unbolted from the original coil...then they tuck the resistor wire away on the firewall where it cant be seen.
I think there is also an original 2nd wire that comes from the starter solenoid and attached to the original coil........the 2nd wire will not be needed with the Peyronix (I think).
Other members feel free to correct my info if necessary
Melting Slicks
Joined: Jul 2005
Posts: 3,389
Likes: 83
From: Norfolk Virginia
If you are still using the stock coil you don't need to change anything. If you purchased their 4500v coil, then you need a full 12 v supply for it. I am running that very setup on my 71 right now.
