Wiring up Sniper EFI. Where did you hook the pink 12v wire

Having issues with finding a place to make a connection for the 12v wire. This is a '72 Challenger 340 with stock electronic ignition. Every wire I test doesn't have 12v cranking and run.

Need to hook it up with a relay hooked to battery power, triggered by the ign switch.

Yep, that is a problem if you try to keep the stock ignition system. There are ways to do it if you're willing to build a little circuitry.

Or you can just ditch the stock ignition system and put in a locked distributor and use the Sniper to control the timing. That is what I'd recommend. Get rid of the ballast resistor and then you can wire J1 and J2 together so you get 12v during start and run. If you want it to look stock you could use a locked out lean burn distributor and then hide the CD box somewhere behind the glove box.

I'd like to see the schematic for that. Seems to me you have to trigger the relay with either J1 or J2. If you tie them together then you defeat the purpose. So I don't see how a relay solves anything.

This question has come up before and the only solution I've seen that appears to work uses a diode to tie the two circuits together without allowing the start voltage to bleed into the run circuit.

Wiring J1 and J2 together seems to overheat the coil and it cuts out. Gets REAL hot.
The relay idea would work by triggering the relay using the 12v starter relay trigger wire (yellow) at the starter relay.
I like the diode idea, but trying to find something where I live is a challenge....no Radio shacks up here.

The relay idea might work if you have the ECU connected to run and then use the relay to also connect to 12v during start. I haven't tried that method but it seems like it might be worth a try. I'm not a big fan though since now you've added another relay to the clutter of the ballast resistor and the confusion of having a J1 and a J2. Why have all of that complexity? The Sniper just needs 12 volts so why make it so complicated.

On my car I just eliminated all of the Mopar ignition monkey motion. I never like the ballast resistor idea anyway or the Mopar ignition box. I also got rid of the voltage regulator and used an internally regulated alternator. The Mopar engineers in the 60's and 70's had a lot of little boxes and things on the firewall and inner fenders. I never like that look. The modern approach is to use the ECU to control all of that stuff and get rid of the analog parts.

Installing a diode between the IGN1 and IGN2 circuits is the simplest way to get a constant key on source. The preferred diode seems to be an IN9004.

Yeah I think that would work if the correct diode is used. I'd say the diode approach is better than the relay approach since it is less complicated and it should last longer.

You get a .7V voltage drop across the diode...if that is only used as a trigger source, it would be OK. However, if the pink wire drives other circuits in the ECU, then it would not be a good idea.

I have the Holley HP, and I just installed a small Painless 4 switch panel under my dash ledge. I know it does not look stock, but for me, it does not matter.

My 2 cents.

Mark

The diode should work as shown above.
On my FiTech, I tied both start and run wires together and that supplies the run power to both the FiTech unit and the MSD 6al ignition box.

I ended up using a relay....12volts from the battery...triggered from the starter relay yellow wire....tied into the blue 12volt run wire at the ballast. Started right up ! I still think I'll source a diode though. I like that better to try and keep the engine compartment as uncluttered as possible. We already have all the Sniper harnesses to add to the clutter!! LOL