Engine wiring

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69Elcamino

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Brought a rat 69 el camino with a 360 in it need any ideas for hooking up the wiring from gm to the 360 block to get ignition to work
 
Welcome aboard

Sounds like quite the project you got on your hands

Can you start a project page so we can see what you got ?

Whats behind the 360?
And whats the plan, 4x4?
 
Here's the thing. Most ignition "run" feeds go dead during start. In factory Mopars this is called IGN1 or "ignition run."

ONLY in Mopars, the power during cranking is provided by the ballast bypass circuit IGN2. This comes from a separate contact on the ignition switch used only for that

On Fords, AMC, and GM the bypass function during start comes from the "I" terminal on the starter relay / solenoid.

So first thing you need to do is see if your GM "run" wire stays hot with key in "start." If not you have a couple ways to go..........

You'll need a starter relay anyway, because of the high current from the Mopar starter. You could use a late model "Jeep" starter relay which has an extra contact If you have an automatic trans, this might be the best way, as it also accomodates the Mopar neutral safety function


298660d1486039071-renix-xj-starter-solenoid-wiring-question-starter-relay-diagram-001.jpg


Or you could wire a big diode from the "S" solenoid wire over to the ignition system

Yet another way, if you don't have an automatic transmission, is use common Ford fender mount relay from the 70's. Use the key to fire the relay, use the big studs to feed the Mopar solenoid, and connect the "I" terminal to the new ignition system.
 
That vehicle would have had points. So all you need to do it follow the wire that went from the + side of the coil back to the bulkhead and cut the resistance wire out. Then run your own standard type wire. The wire will look different than all the others. The resistance wire has a cloth type covering. GM ran the resistance wire all the way through the harness to drop the voltage at the coil so the points and coil didn't burnt up. There may have been two wires on the + side of the coil. The second came from the starter solenoid. Sometimes both wires were together in one connector on the coil. As long as the wire you run stays hot with the key in the run and start positions you are good to go.
 
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If you look at the top connector of the coil in this picture you will see what I'm talking about. The cloth looking wire is the one you're looking for. That is the resistance wire that comes from the switch.

coil wire.jpg
 
There's another way around the resistance wire. You can use the resistance wire to fire a relay and use that to provide the "run" voltage. "I bet" it still goes dead in "start" and you have to deal with my original post above^^
 
Yes a relay would would work and no it does not go dead in the "start" position on a GM. They use a second wire up from the starter solenoid to give the coil full battery voltage in the start position.
 
Yes a relay would would work and no it does not go dead in the "start" position on a GM. They use a second wire up from the starter solenoid to give the coil full battery voltage in the start position.
Cool thanks for the heads up and my hei will be here Tuesday
 
Yes a relay would would work and no it does not go dead in the "start" position on a GM. They use a second wire up from the starter solenoid to give the coil full battery voltage in the start position.

You sure? I used to have a column lock column in my old Landcruiser from about a 70 GM and it certainly did. That old girl had various, a 360, a 340, and 318 before I gave it all up

I already explained the solenoid "I" wire. It does exactly the same job as IGN2 in a Mopar
 
I just did this on a 69 Camaro the weeks ago. One wire to the coil was hot with the ignition in the run position the other was only hot in the start position.
 
I ended up with the car because it did not run right. Someone else put the HEI in it and just reused the resistance wire. All I did was cut off the wire coming up from the starter. Then pulled the bulkhead, cut the resistance wire out and ran my own. It stayed hot on that car. Maybe an El Camino is different? IDK
 
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Come to think of it you could still put the wire on coming from the starter back on. Should not make any difference.
 
I ended up with the car because it did not run right. Someone else put the HEI in it and just reused the resistance wire. All I did was cut off the wire coming up from the starter. Then pulled the bulkhead, cut the resistance wire out and ran my own. It stayed hot on that car. Maybe an El Camino is different? IDK
Nope el camino is the same mine is hot all the time
 
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