12 volt constant Source

[DblR]

Hello guys, I've managed to hook up the master kit Fast EFI I bought in june 23. I could never find a 12v constant wire to hook up the EFI. I finally just hooked fuel pump and EFI wires directly to battery. Yes it works but not with ignition switch and I'd like that. The 72 ignition system was changed. If anyone can help me out it would be appreciated. Thanks in advance.

 

[BeepBeepRR]

If you are actually looking to switch the EFI on with the key then Check the brown wire at the ballast resistor. See if its switched I believe it is.

 

[DblR]

Sounds to good to be true but I'll try that. Thanks

 

[matthon]

I installed a ground and positive hub under the dash, as well as a ground hub next to the battery.
No more running/splicing wires together, bad connections, multiple wires on the battery terminals, etc.

Iirc, I ran both the ignition and start wires to the positive hub, I have an electronic distributor, it also has the voltage gauge on it.
All screwed down with round connectors and sleeves on the wires.
Good solid connections on expandable hubs.

 

[451Mopar]

If the switch is like on my 1969 Coronet, Example: the ballast resistor start and run connections can be connected together. The power to the starter relay is a different circuit in the ignition switch. It might be better to connect the start and run wires together after running through diodes one for each start and run wire from the switch, and use that to trigger two relays. One for clean ECU power, and the other relay to supply the Engine compartment and charging system power (if using the stock type alternator / regulator and not a one wire alternator. That might help isolate some ignition and alternator noise from the ECU power-on line? That assumes power to each relay is run direct from (or as close to) the battery. Not sure if adding a capacitor after the diodes where connected to the relay trigger might maintain the relay power for a few mill-seconds if there is a slight break in power between the start and run key positions? Timing would depend on the current draw of the relays and the size of the capacitor.
I would think the EFI box also has some filtering on the power-on trigger side of the box to prevent short power upsets?

 

[kiwigtx]

I installed a ground and positive hub under the dash, as well as a ground hub next to the battery.

That's a good idea. I did something very similar to my A100 under the dash....made the re-wire a lot easier.