switched 12v source for my Holley Sniper

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Slappy

Slappy

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I am installing a holley sniper on my Demon. This requires a switched 12 v source that stays hot during cranking and running. Everything off my ignition switch dies during crank or is only hot during cranking. Any ideas where i can find this source ? Should I just do a toggle switch type thing? Holley says this wire should not be piggy backed with other things. Forgot to mention i have installed a aftermarket kwik wire harness throughout the car.
 
Read that thread^^^ There is no magic wire. The ignition switch only has 4 outputs
1...ACC hot only when key is in "accessory" powers things like radio, wipers, etc
2...Start--usually yellow, only hot when key is twisted to "start" and fires starter relay and starter
3...IGN2 the bypass circuit, usually brown. This is a separate switch contact than "start" but is also hot "in start". It goes to the coil + side of the ballast resistor and FEEDS THE COIL HOT VOLTAGE when in "start." IT is the ONLY source of ignition power during start/ cranking
4....IGN1 or "ignition run." This is hot ONLY in the "run" position and goes COLD during "start" or cranking.

Usually with no ballast type ignition, jumpering IGN1 and IGN2 together will do the job
 
67Dart273 said:
Read that thread^^^ There is no magic wire. The ignition switch only has 4 outputs
1...ACC hot only when key is in "accessory" powers things like radio, wipers, etc
2...Start--usually yellow, only hot when key is twisted to "start" and fires starter relay and starter
3...IGN2 the bypass circuit, usually brown. This is a separate switch contact than "start" but is also hot "in start". It goes to the coil + side of the ballast resistor and FEEDS THE COIL HOT VOLTAGE when in "start." IT is the ONLY source of ignition power during start/ cranking
4....IGN1 or "ignition run." This is hot ONLY in the "run" position and goes COLD during "start" or cranking.

Usually with no ballast type ignition, jumpering IGN1 and IGN2 together will do the job
Click to expand...

E3B7069F-E290-4C04-BD63-BDAD50298928.png
 
This what I did . Per Holley and it worked perfectly . The relay is turned on with a wire off the ignition . Once the relay is on it stays on during cranking and run . Turns off when the engine is turned off . 12v source does not have to be constant only when ignition is turned on initially before cranking. Got a basic relay and pigtail off Amazon for $10
 
Must be a special "latching relay". If using a modern ignition like HEI, Pertronix Ignitor II/III, or MSD, you don't need the ballast resistor, so can just jumper across it to get 12 VDC all the time on the IGN wire (or IGN2 wire since both are now connected). If using the 1970's Mopar ignition or even early aftermarket like Crane Cams XR700 or original Ignitor, you must use the ballast. Later HEI has electronic "dwell control" so doesn't need (or want) a ballast.
 
Slappy said:
This what I did . Per Holley and it worked perfectly . The relay is turned on with a wire off the ignition . Once the relay is on it stays on during cranking and run . Turns off when the engine is turned off . 12v source does not have to be constant only when ignition is turned on initially before cranking. Got a basic relay and pigtail off Amazon for $10
Click to expand...

Do you have IGN1 or IGN2 going to the 86 pin? I'm about to install a sniper using my factory wiring and ignition system.
 
This question comes up time and time again, short of taking an ignition switch and ringing it out I have always assumed that the IGN2 had 12v in run AND start. How else would the coil get power during cranking? My Mopar ignition module is powered off the blue wire (IGN2) and I'm pretty sure it needs power during cranking.


Alan
 
Cuda Al said:
This question comes up time and time again, short of taking an ignition switch and ringing it out I have always assumed that the IGN2 had 12v in run AND start. How else would the coil get power during cranking? My Mopar ignition module is powered off the blue wire (IGN2) and I'm pretty sure it needs power during cranking.


Alan
Click to expand...
No it works exactly as I explained. Please go re-read post 4

The IGN1 is the "run" source and is hot ONLY in run
The IGN2 works just like the "start" contact except it is a separate switch contact, and is hot ONLY in start

The IGN1 originally supplied power through the firewall to the VR, alternator field, choke if used, smog devices if used, AND THE IGNITION SYSTEM

IGN2 comes "on" when key is twisted to start and feeds power direct to the coil during that time.
 
I may have miss labeled the blue as IGN2, the blue is IGN1


I just put a meter to an ignition switch (1969) on the bench.

Accessory (Full left)
BAT-ACC

Off
No connections

Run (First right)
BAT-ACC-IGN1

Start (Second right, with spring)
BAT-IGN1-IGN2-ST

The Blue (IGN1) is hot during both Run AND Start
The Brown (IGN2) is hot only on Start


As I said my ignition module is powered off the blue wire and must have power during cranking to start.
I could go out to my Barracuda and try it on a 67 but I see no reason for it to be different. I've setup four different cars this way, three 69s and a 67

All you need to do is hook a meter up to the blue wire at the ballast and put the meter on the cowl and start the car (unplug the wires from the ballast for an accurate test).

It is how I hotwired my 69 so the body shop could fire it up (all underhood wiring is gone (no charging circuit)), battery to left switch (BAT) connects to (IGN1) that connects both poles on the right switch and to the ballast. When that switch is turned on (momentary) in connects the blue wire to a wire going to the starter relay and a brown wire going to the other side of the ballast (the coil side).
IMG_5877.JPEG



Alan
 
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I can guarantee you that is an anomaly. Is the switch completely disconnected from the circuit? If you made those measurements with it wired in, the IGN1/ IGN2 will feed back to each other
 
Ok, I re-ran the bench test and I must have not had the switch fully switched, it is a new switch so I put the cylinder in and did it again, you are correct, IGN1-Blue in Run only and IGN2-Brown in start only.

So I go back to my ignition module installation on the blue side of the ballast 12v on run, if there is no voltage on the blue from the switch on start then the ignition module is getting a reduced voltage through the ballast from the IGN2-Brown wire. For 20 years I have assumed that the IGN1 was hot during cranking because my ignition module is getting power, this is the first time I have actually tested the switch and thought this through.

So back to the question of power on both run and start I would say hook up to the blue (IGN1) it will get power (although reduced, probably enough) through the ballast. If there is no ballast then you could just tie the brown and blue wires together. In run the ST and IGN2 are not connected in the switch so no back-feeding to the starter relay from the brown wire.


Alan
 
Well yeah that's kinda what was said. Here is how it works with the factory breakerless ECU which is a real head scratcher. The ECU and the coil must get power to start of course. With IGN1, the only power to the system is the brown going to the COIL side of the ballast So during cranking, the coil does get hot full battery voltage

But the box.........LOL...........is fed BACKWARDS (so to say) from the brown IGN2---through the resistor---to the ign1 side of the ballast, and from the wiring harness back into the box. This means that the box is getting reduced voltage during starting!!!. Not only is the battery dragged down to 10.5--11V during cranking, but the box is only getting power from the resistor. I've never measured just what this is, I would guess 6-8V or so
 
low_kota said:
Do you have IGN1 or IGN2 going to the 86 pin? I'm about to install a sniper using my factory wiring and ignition system.
Click to expand...
Can you update on how you hooked up your sniper please? I’m using stock ign also
 
Slappy said:
This what I did . Per Holley and it worked perfectly . The relay is turned on with a wire off the ignition . Once the relay is on it stays on during cranking and run . Turns off when the engine is turned off . 12v source does not have to be constant only when ignition is turned on initially before cranking. Got a basic relay and pigtail off Amazon for $10
Click to expand...
So you eliminated the two prong ballast tied those wires together ran battery voltage with the key on ground and pink wire?
 
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