Switched power source for sniper install?

[panteramatt]

So where in my 74 can I find switched power in both run and start?

Ok so bumping this back up due to needing to find another switched source. Im usung the green with red stripe wire which give power to my sniper in the key on position. I need a source that will give me power with key on and acc so I can download new software.

 

[Smedley]

I have a Centech wiring harness, for my Fitech Install I used a green wire labelled IGN AUX on the pside loom. I called Centech and talked through it with them. Seems to work well.

 

[panteramatt]

Well that dont help I have the stock harness

 

[DirtDonk]

Same wire though, just a different way.
Your Green w/red stripe wire from the voltage regulator is hot in ON/START, as is the Red w/green wire to the ignition coil. However I usually recommend against tapping into the ignition wires for anything, even a computer.
The voltage regulator wire can handle it.

What modifications, if any, are you working with regarding your wiring harness? Still bone stock? Upgraded alternator? Anything else?

In a pinch the Bronco "I" wire on the starter relay is hot in both ON and START as well.

Paul

 

[migs]

On my 1970 used the existing factory resistor coil wire to trigger a relay to provide a full 12 volts during run and start. Here's a link to a post I had about the wiring and relays:

sniper relays

It's actully triggering two relays, the other one sends power to the distributor. going on a year now since installed, still working great!

 

[panteramatt]

Bronco electrical is bone stock

 

[Broncobowsher]

The "I" wire on the solenoid is just as bad as pulling power off the ignition (positive at the coil). Because it is the same.

The switched power at the voltage regulator mentioned above is the best choice. Good spot since you will be running the power and ground wires to the same location.

This is one of those spots where I will recommend against adding a relay. The switched power is just a signal wire, the big wires off the Sniper are where the load is at. The result, the ignition wire is effectively just running a relay in the Sniper anyway. Adding another relay to trigger the internal relay just adds more junctions, splices, contacts, coil, all points of failure. More likely to cause more problems than it will ever solve.

 

[panteramatt]

What's the best way to tap into the green/red voltage reg wire? I have wire taps but I wouldn't trust those for such an important job. I know I can pull the sheathing back on the wire and solder the pink wire into it but I'd rather not.

 

[panteramatt]

Got another question. Just looked at my reg and the I spot on it isnt used and the green with red stripe wire is in a harness behind it that goes to a large round brown plug

 

[DirtDonk]

The I wire is not used on our regulators. Ford had two (that I know of) wiring schemes for externally regulated alternator systems, where vehicles that had ammeters, like in our case, only three positions are utilized. Where the vehicle has indicator lamps on the dash instead, all four positions are used as in most of the older diagrams.
Has lead to many incorrectly installed electrical systems even by professionals.

So yours is correct.

No idea what the brown plug might be. Got pics you can post up? Being a '74 it's going to have at least a few of what we commonly call "Dura Spark type" type connectors at various places in the harness. Including for the alternator harness and obviously the ignition harness too.
But pics would surely help anyway. Besides, everybody likes to see stock unmolested wiring as a reference.;D

Not sure what the best way to tap into the wire is. Maybe someone will chime in with their recommendations.

Paul

 

[panteramatt]

[URL=http://s613.photobucket.com/user/panteramatt/media/20190426_165838.jpg.html] [/URL]

 

[DirtDonk]

Thanks Matt. Yep, that's all that is. Just one of the factory connectors ('73 and later) for the charging system. The large gauge Black w/yellow wire should connect straight to the alternator at one side and the other goes into the cabin, feeds all the electrical system then back out to charge the battery.
Green w/red runs straight to the ignition switch.

Is the third wire another large Black wire? If so it's just the other end of that charge wire loop heading back out to the battery.

Paul

 

[panteramatt]

Thanx a lot paul! Did I read somewhere I could tap into the brown wire on the starter solenoid?If thats true I could just use a ring terminal

 

[panteramatt]

BTW Im running all of your fuel system. How loud is your external pump?

 

[DirtDonk]

Thanx a lot paul! Did I read somewhere I could tap into the brown wire on the starter solenoid?If thats true I could just use a ring terminal

You heard it here!;D
But 'bowsher has good points about using it because it's the same as using the Red w/green wire at the ignition coil in some respects. Same as I mentioned in the same breath practically, as saying not to use the Red w/green coil wire.
However lots of people have done just that (ring terminal on the I post) and so far have not had any issues for use with the modern computers.
Not sure if anyone has had trouble using it for other things, but there may be some mitigating circumstances too.

For example, will you have the computer controlling the ignition timing? If so, does it control the coil directly? If so then there is nothing really to hurt by utilizing the Brown I wire.
I'm just not sure how the Sniper works the ignition. Or if you're even using it for that?

Paul

 

[DirtDonk]

BTW Im running all of your fuel system. How loud is your external pump?

Thanks!
Well, "your results may vary" seems to work well here.
Some of it depends on how it's mounted of course, and where. But I think that just like other pumps there are some you can hear more than others.

My take from other customers is that no matter what you usually hear the frame mounted pumps at least a little. Can't hear it when the engine is running and you're driving down the road, but just turning the key on you can hear it spool up.
And if you mount it loosely, or worse still, to some body sheet metal, you're going to hear it a lot more.

It's the reason internal tank mounted pumps are getting more and more popular even with retrofit kits.
But let us know here when it's up and running how loud it is. If it's obnoxiously loud and you have it mounted properly, there might be an issue we need to take care of at our end.

Oh, noisy or not, make sure it's pumping liquid gas and not some air! Air can make for a wicked loud and obnoxious sounding pump.

Paul

 

[panteramatt]

Bumping this back up. Please read edited first question.

 

[Broncobowsher]

There is no place that is hot in Acc, run, and start.
Just program with the key in the run position.

 

[panteramatt]

Ok, that sucks cause Im having issues with it constantly pumping fuel into the motor. Ill just connect the power straight to battery for initial startup.

 

[Broncobowsher]

Unplug the fuel pump relay.

Something is very wrong. The fuel pump should only cycle for about 4 seconds (longer than OEM systems) and turn off until it reads a tach signal. And the injectors should not be dumping any fuel in either. I would be surprised if there is a reprogram that fixes this. Probably a bad ECM in the throttle body.