12V ignition switched wire

[davesb372]

Hello,
I bought a Ready to Run electronic distributor for a '71 340 that I'm putting in my '72 Challenger, the car came with a 318 with points. What wire should I use that is switched by the ignition to power the coil. I attached their wiring diagram. Thanks for any help.

 

[quapman]

The blue wire that powers the choke thermostat is on with the key. Your 72 might not have a choke-t-stat, but the blue powers other things as well. I don't recall which terminal # it comes out of.

 

[70Barracuda]

On mine it's the blue w white stripe and brown is 12v cranking.

 

[davesb372]

Thank you.

 

[Heywodja]

Does the blue wire also have 12 volts while cranking? Or do the blue one and brown one both need to be connected? Just so happens that I have the same situation installing a ready to run in my big block..

 

[quapman]

Blue should have power when cranking, yes. Never connect the blue and brown. (Kind of like "Don't take the brown acid.")

 

[Heywodja]

I think I verified that the blue one does not have power while cranking. The brown one was on opposite side of the resistor, and it went to the coil positive.
I cyphered that they were connected in a way, but the brown one just received the reduced voltage...

 

[70Barracuda]

Brown is 12v crank Blue is 12v key on. For Fitech EFI they both are put together.

 

[Heywodja]

Ok thanks!

 

[quapman]

You learn something new all the time.

 

[Cudafor36]

Diagrams attached