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Anyone want to make a few $$$s? Advice on Sniper install

kaj750

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1. I'm new to building cars this old. I've spent my life working on anything from the 90s and later.
2. I'm still learning the vocabulary, so when I hear ammeter, I don't know where or what it is LOL (I assume it's the actual gauge in the cluster).

So, I have a Sniper 2 installed on my '69 Charger and need to figure out the wiring. My car appears stock. I can't really confirm as I'm uneducated on the subject, but I even have the resistor on the firewall for the distributor and all wiring seems really, really old and original. See pic below for reference (the mystery wire tap has been removed and wiring seems to be okay).

3. I bought the PDM for the Sniper and am aware to get power from the alternator side, vs the battery side. So, do I just grab power from alternator post? If so, don't I already have a mess of wires on it (see pics below) There are two leads coming off the alternator post, now. One lead goes towards a module on the engine side of the radiator support, above the passenger headlight. The other lead goes back into the harness and up towards the firewall. Is it safe to add another wire? Pic below for reference.
4. If I run power from the alternator to the PDM, how does the fuel pump and Sniper ECU, which run off the PDM get power to start the car? It will have a 30a fuse inline and 10g wire.
5. The PDM needs switched power. I can just run it from the "radio" spot of the fuse box?
6. My water pump has a port on top. I thought it was 3/8" so that I could install my coolant temp sensor, but it looks quite a lot bigger than 3/8". Can anyone confirm? Pic below for reference. If it won't work, then I'll be adding an adapter plate to the thermostat housing with a 3/8" port. I just don't like the idea of another potential spot for leaks. I do not know which part number water pump I have, but it looks to have one on the front. I can get it, if needed.
7. I plan to run a 10a fuse from the PDM to the fuel pump. Overkill? Will also use 10g wire.
8. Where exactly do I want to get the tach signal for the Sniper? Negative post on the coil? I see a brown wire that I believe is the tach signal for the gauge cluster.

These are the last things holding me up from starting the car. I don't expect anything for free these days, so would be willing to pay someone to walk me through this. I can't imagine it would take more than an hour or two at the most. If it's easy to explain everything in text, then I'm fine with email/text/etc. Phone works for me, also. I've built lots of cars and helped run a shop, so I'm not a complete dunce, I just don't THIS car. It does have a way of making me dumb LOL
I've had a few people in my town promise to help but then flake on me. I just want to get the car finished so I can enjoy it again. It's beyond frustrating to have a car so close to being done but sitting and collecting dust.

Anyone willing to help me out? I'm hoping to have it done Thurs Apr 18 or the 19th. Short notice, I know, but I leave town for 10 days on Sat and would sleep better knowing the car is wired up first.

Please let me know ASAP. Thank you, in advance. Pictures of resistor, alternator post, and water pump port:

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Give this document a good read - from Holley.

there are wiring diagrams towards the end of the document.
it explains most of the questions you are asking -



but -
1. the ground wire and constant power source must be made directly at the battery terminals. Do not use an alternator post for power - could get back feed and voltage irregularities.
2. switched power should come from the ignition switch - or a non fused connection on the fuse block. really would not tie the switched power into the 10A radio.

hope the PDF that is attached will help some.

Bill
 

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First, read that doc @72ls5fla attached. Also, check out the sniper forum on forums.holley.com.

For now, here are a few comments... (also, double check the terminal numbers I'm offering... all this should be in the PDM document and on the sticker on the back.)

3. I bought the PDM for the Sniper and am aware to get power from the alternator side, vs the battery side. So, do I just grab power from alternator post? If so, don't I already have a mess of wires on it (see pics below) There are two leads coming off the alternator post, now. One lead goes towards a module on the engine side of the radiator support, above the passenger headlight. The other lead goes back into the harness and up towards the firewall. Is it safe to add another wire? Pic below for reference.

Ok. Not sure who said connect to the ALT... you definitely don't want to do that because you will get a ton of interreference. You connect the red wire from the 16 pin connector directly to the battery. The same for the black wire - goes directly to the battery. Both must be connected directly to the battery terminals. So.. IMPORTANT - I'm actually not fan of the PDM, but you're using it.... So, speaking in PDM terms... you connect the PDM directly to the battery for both the pos and neg using the terminals at either end (unnumbered) in the PDM - it has to b connected DIRECTLY. Then connect the red wire from the 16 pin connector from the ECU to terminal 5 on the PDM and the black wire to terminal 8 on PDM.

4. If I run power from the alternator to the PDM, how does the fuel pump and Sniper ECU, which run off the PDM get power to start the car? It will have a 30a fuse inline and 10g wire.

First, please d not run anything off the ALT... not only bad karma, but it create EM noise and that will fuk up the ECU. Run the full pump power to it's own power source OR when using the PDM to terminal one (1) on the PDM, and it is turned on by the ECU via the BLUE wire which is - in some cases - connected to the ground on the fuel pump. In this case using the PDM... run a red wire from the fuel pump to termainal 1 and a black ground wire from the pump to terminal 2 on the PDM, and the BLUE wire from the ECU 16 pin to terminal 3 on the PDU. The ECU controls the fuel pump.

The trick is the ignition... you have to get rid of the resistor, connect those two wires to at least the PINK wire when not using a PDM. You have to bridge them because 1) it must stay 12v+ and the resistor will push down to 9v or less, 2) it must be 12v+ during cracking and in Mopar that is a separate wire... hence two... so connect both to the ignition switch wire from the 16 pin connector. HOWEVER... all this depends on your ignition box and/or distributor and the fact that you're using the PDM. So, I can't help without that info.


5. The PDM needs switched power. I can just run it from the "radio" spot of the fuse box?

Please don't do that. PDM is connected directly to the Batt. See the top unnumbered terminal. The wires from the resistor (which go to the ignition switch, generally speaking) go to the termainal(s) in the PDM. Since I'm not an expert with PDM... and don't know the ingnition system you have... so I'm not much help for you here.

6. My water pump has a port on top. I thought it was 3/8" so that I could install my coolant temp sensor, but it looks quite a lot bigger than 3/8". Can anyone confirm? Pic below for reference. If it won't work, then I'll be adding an adapter plate to the thermostat housing with a 3/8" port. I just don't like the idea of another potential spot for leaks. I do not know which part number water pump I have, but it looks to have one on the front. I can get it, if needed.

Get a 3/8 NPT to 5/8 NPT adapter. No way around that really, given your current setup. Honestly, I would worry about leaks... NPT threads have been around since 1864 and don't leak readily.


7. I plan to run a 10a fuse from the PDM to the fuel pump. Overkill? Will also use 10g wire.

Depends on the fuel pump. But if it's the one in the kit, 14ga is the "default" 10ga is fine, but could be over kill. 10amp fuse should be ok. You'll know pretty quickly if it's too small :)


8. Where exactly do I want to get the tach signal for the Sniper? Negative post on the coil? I see a brown wire that I believe is the tach signal for the gauge cluster.

There is a GREY wire from the ECU... that goes to the tach, assuming the tach is analog...
 
Thanks for the replies, guys!

I clicked on the link. I have those instructions, they came with the kit. I understand how the EFI works, along with inputs and outputs. My problem is that I don't know where on the car to find a safe place to tap everything into. My lack of knowledge is with the car, not the EFI kit. This is my first time working on a car with limited electronics and working with a complicated electrical/charging system such as what Chrysler uses.

Soooooo....

3. I'm told NOT to use the battery as a power source because of the way my car's charging system works. I did some research and believe what I was told. My fuel pump was previously running off the battery (via relay/switch) and the amp gauge in the car was constantly showing a charging state. It was never at "0". This concerns me as I've seen what happens when too much is run off the battery and the elevated current from the alternator is sent through back through the system and to the battery. Looking back at my notes, I see I was told to take power from the "alternator side" of the charging system. I guess I misunderstood what that meant. I wouldn't know where else to get power from.

4. Noted on the PDM wire locations. When you say to delete the resistor, do you mean the one on the firewall from my first picture, above? My distributor will still work okay? I have a Mallory Unilite distributor with everything else OEM, as far as I know. Do I just essentially butt connect the blue and brown wires together with the ignition wire from the 16-pin connector?

6. 5/8" -> 3/8" NPT adapter. Check. Looks like I have room for all of that. Not worried about NPT leaking, I was worried about adding a thermostat housing adapter and have it leak somewhere between the water pump and thermostat housing. I trust the gasket to adapter and suppose the o-ring between the adapter and thermostat housing would be fine, but meh. I dunno.

7. I can use 14g wire for fuel pump. Got it. With fuse.

8. Wire was dirty. Grey wire goes from the (-) post of the coil to the OEM analog tach. If I use that wire for the Sniper kit, then how would my OEM tach still work? Can I just run an additional wire from the (-) post to the ECU?

Thank you for the help. I've had the WORST time finding help with anything related to this car. Not a lot of people know the ins and outs of these things and those that do aren't the most willing. I've almost sold the car twice now, out of pure frustration. I love the car and planned to be buried in it, but it doesn't do me any good if I can't get it running.
 
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3. I'm told NOT to use the battery as a power source because of the way my car's charging system works. I did some research and believe what I was told.


---Yeah… you really want to connect directly to the battery. Frankly, your charging system is connected to it, but via other systems, etc. Also, if you’re charging system is doing something weird, you might have bigger problems. The Sniper ECU is voltage sensitive… especially during cranking. If not connected to the battery you’ll have issues from misses to hard starts. The ECU wil be fine connected to the battery. the only caveat is if your charging system is messed up and is over charging or spiking.

My fuel pump was previously running off the battery (via relay/switch) and the amp gauge in the car was constantly showing a charging state. It was never at "0". This concerns me as I've seen what happens when too much is run off the battery and the elevated current from the alternator is sent through back through the system and to the battery. Looking back at my notes, I see I was told to take power from the "alternator side" of the charging system. I guess I misunderstood what that meant. I wouldn't know where else to get power from.


---You want the pump running off the batt via a fuse/relay, so that’s fine! Also, that is effectively what the sniper ECU is doing for you moving forward. Th The ECU will act as a ground activated relay. The Alt meter should never say “0” if the engine is running, which that’s good too. If you’re having issues with draw from the batt… you likely have a batt issue. Might need to check your total draw on the batt with everything running – easy to do. At the end of the day - - when it comes to EFI… you pretty much have to connect directly to the batt. And the same goes with any digital ignition system.

4. Noted on the PDM wire locations. When you say to delete the resistor, do you mean the one on the firewall from my first picture, above?

---Yep. You need 12v with ignition on and during start. Mopar provides 12v only during cranking and then less – using the resistor – to the distributor/coil during run. EFI needs a constant 12v. And a clean 12v during cranking.

My distributor will still work okay? I have a Mallory Unilite distributor with everything else OEM, as far as I know. Do I just essentially butt connect the blue and brown wires together with the ignition wire from the 16-pin connector?

----Yep. But in that manual… there are instructions for each type of ignition. You basically have a "ready to run" distributor, meaning the ignition box is in the distributor. You should have three wires coming out of it. You want to follow the instructions for that distributor. It's SUPER easy with that distributor, it's just power, coil and ground... but you have to connect the wire from the ECU to the wire from the distributor that is at the negative pole on the coil. I'm 99% certain it's the yellow wire from the 16pin connector.. that goes to the negative pole on the coil.

HOWEVER... your kit may have a "three pin" connector hanging out the back of the collection of wires coming out of the 16 pin connector. Unless you have a separate controller, do not plug this into the three pin coming out of the distributor. Very important. Once you're good to go, we can come back to this topic.


6. 5/8" -> 3/8" NPT adapter. Check. Looks like I have room for all of that. Not worried about NPT leaking, I was worried about adding a thermostat housing adapter and have it leak somewhere between the water pump and thermostat housing. I trust the gasket to adapter and suppose the o-ring between the adapter and thermostat housing would be fine, but meh. I dunno.

---Gotchya... You’ll be only working with the waterpump housing.. the water pump remains untouched. It's pretty straightforward. But know this... temp is crazy important for the ECU. You can't run without it.

7. I can use 14g wire for fuel pump. Got it. With fuse.

----Whatever the pump requires. Be sure to check the documentation for the manufacturer. I just assumed your pump is part of the sniper 2 kit… but double check and confirm amp draw.

8. Wire was dirty. Grey wire goes from the (-) post of the coil to the OEM analog tach. If I use that wire for the Sniper kit, then how would my OEM tach still work? Can I just run an additional wire from the (-) post to the ECU?

---Ah.. so you’re using the OEM tach in the dash? If the tach is already connected to the coil, leave it for now and it should work fine… the signal will come from the coil and not from the ECU, which is essentially controlling the coil anyway (remember the yellow wire?). In short, for now leave it and if the tach isn't working, we'll come back to it. Basically, I'm working off your description and a few pics:) Anyway... I tihnk it'll work as is, presuming it did before.

Thank you for the help. I've had the WORST time finding help with anything related to this car. Not a lot of people know the ins and outs of these things and those that do aren't the most willing. I've almost sold the car twice now, out of pure frustration. I love the car and planned to be buried in it, but it doesn't do me any good if I can't get it running.

---Don’t sell it! There are tons of people on this forum ready to help and they're all a lot smarter than me.
 
3. I'm told NOT to use the battery as a power source because of the way my car's charging system works. I did some research and believe what I was told.


---Yeah… you really want to connect directly to the battery. Frankly, your charging system is connected to it, but via other systems, etc. Also, if you’re charging system is doing something weird, you might have bigger problems. The Sniper ECU is voltage sensitive… especially during cranking. If not connected to the battery you’ll have issues from misses to hard starts. The ECU wil be fine connected to the battery. the only caveat is if your charging system is messed up and is over charging or spiking.

My fuel pump was previously running off the battery (via relay/switch) and the amp gauge in the car was constantly showing a charging state. It was never at "0". This concerns me as I've seen what happens when too much is run off the battery and the elevated current from the alternator is sent through back through the system and to the battery. Looking back at my notes, I see I was told to take power from the "alternator side" of the charging system. I guess I misunderstood what that meant. I wouldn't know where else to get power from.


---You want the pump running off the batt via a fuse/relay, so that’s fine! Also, that is effectively what the sniper ECU is doing for you moving forward. Th The ECU will act as a ground activated relay. The Alt meter should never say “0” if the engine is running, which that’s good too. If you’re having issues with draw from the batt… you likely have a batt issue. Might need to check your total draw on the batt with everything running – easy to do. At the end of the day - - when it comes to EFI… you pretty much have to connect directly to the batt. And the same goes with any digital ignition system.

4. Noted on the PDM wire locations. When you say to delete the resistor, do you mean the one on the firewall from my first picture, above?

---Yep. You need 12v with ignition on and during start. Mopar provides 12v only during cranking and then less – using the resistor – to the distributor/coil during run. EFI needs a constant 12v. And a clean 12v during cranking.

My distributor will still work okay? I have a Mallory Unilite distributor with everything else OEM, as far as I know. Do I just essentially butt connect the blue and brown wires together with the ignition wire from the 16-pin connector?

----Yep. But in that manual… there are instructions for each type of ignition. You basically have a "ready to run" distributor, meaning the ignition box is in the distributor. You should have three wires coming out of it. You want to follow the instructions for that distributor. It's SUPER easy with that distributor, it's just power, coil and ground... but you have to connect the wire from the ECU to the wire from the distributor that is at the negative pole on the coil. I'm 99% certain it's the yellow wire from the 16pin connector.. that goes to the negative pole on the coil.

HOWEVER... your kit may have a "three pin" connector hanging out the back of the collection of wires coming out of the 16 pin connector. Unless you have a separate controller, do not plug this into the three pin coming out of the distributor. Very important. Once you're good to go, we can come back to this topic.


6. 5/8" -> 3/8" NPT adapter. Check. Looks like I have room for all of that. Not worried about NPT leaking, I was worried about adding a thermostat housing adapter and have it leak somewhere between the water pump and thermostat housing. I trust the gasket to adapter and suppose the o-ring between the adapter and thermostat housing would be fine, but meh. I dunno.

---Gotchya... You’ll be only working with the waterpump housing.. the water pump remains untouched. It's pretty straightforward. But know this... temp is crazy important for the ECU. You can't run without it.

7. I can use 14g wire for fuel pump. Got it. With fuse.

----Whatever the pump requires. Be sure to check the documentation for the manufacturer. I just assumed your pump is part of the sniper 2 kit… but double check and confirm amp draw.

8. Wire was dirty. Grey wire goes from the (-) post of the coil to the OEM analog tach. If I use that wire for the Sniper kit, then how would my OEM tach still work? Can I just run an additional wire from the (-) post to the ECU?

---Ah.. so you’re using the OEM tach in the dash? If the tach is already connected to the coil, leave it for now and it should work fine… the signal will come from the coil and not from the ECU, which is essentially controlling the coil anyway (remember the yellow wire?). In short, for now leave it and if the tach isn't working, we'll come back to it. Basically, I'm working off your description and a few pics:) Anyway... I tihnk it'll work as is, presuming it did before.

Thank you for the help. I've had the WORST time finding help with anything related to this car. Not a lot of people know the ins and outs of these things and those that do aren't the most willing. I've almost sold the car twice now, out of pure frustration. I love the car and planned to be buried in it, but it doesn't do me any good if I can't get it running.

---Don’t sell it! There are tons of people on this forum ready to help and they're all a lot smarter than me.

Now I think I'm getting it, thanks.

4. So, with the Sniper kit, the resistor is no longer needed. Does that mean I shouldn't have been using the resistor with the Mallory distributor? I ask because someone once asked me if I needed it and I didn't know how to answer, only that it's on there now so I assume it's needed (the car is just how I bought it). So the two wires from one side of the resistor will go together as mentioned and I will then delete the wire coming off the other side and going to wherever (I haven't traced it's destination, yet).

8. Yep. I have the OEM tach working. So leave the gray wire attached so the OEM tach works, then the (possible) yellow wire goes where the instructions say in order for the ECU to receive signal.

Okay, that's much better. Knowing it's okay to go to the battery side solves 75% of the issues I was having. In that case I can follow the instructions more closely. I was stuck with "well, this tells me to use the battery but I'm told not to, so now what?". LOL.

Awesome. Now I'm fired up and gonna go start on the car right now. Thank you, very much. I'll report back. And I wasn't kidding about the "nothing is free" thing. I'm more than willing to PayPal you something as a Technical Advisement fee :D
 
I use a separate relay and fuse panel for my Sniper 2. Main power and ground are directly to the battery as per instructions. I wired in a 2post generic starter relay which seems to last longer than the factory style that is sourced from who knows where.

This works and doesn’t cost much compared to the power module.
12 volts of clean power is mandatory to make this system work. I put the coolant sensor in the extra hole near the thermostat with an adapter and it works perfectly and no leaks. Hope this helps and lay out your wiring in stages and take your time. Be prepared to shield your wiring and/or rearrange as needed.

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Update: so, this isn't looking too bad. Since I don't have to worry about the power and ground, I am mounting the PDM over on the firewall where the resistor was.
And then brought the wiring harness from the EFI to that side which is good because that's where my coil is to run the yellow wire, power, ground everything. Right in one spot for the most part.
I'm finding that the PDM is not necessary, but I like the idea of it working as relays for everything, basically. I.E. power and ground is already there for fuel pump, switched source, fires up the fuel pump, etc. I like it. I had a switch wired to the interior the car for the fuel pump. It triggered a relay and the engine bay that fit power to it. Was nice to get rid of all that.
Having LEDs to monitor operating conditions and fault is kind of nice too.

I'll do some more work on it tomorrow. Should have all the wiring done.

Now that the resistor is gone, does anybody know how that affects my distributor?

Also, I am told to run the two power wires (blue and brown) from the resistor to the pink wire on my EFI harness, but what about the leftover resistor wire? The one from the other side. I believe it's black. Do I just leave it unplugged?
And does all of that mean that I should not have been running the resistor with my distributor? Mallory Unilite.
**EDIT** My instructions say that my distributor definitely needs the resistor. So do I just run a wire off of the side of the resistor with the two wires?.


20240418_210532.jpg


Lastly, now that the resistor is gone, can I use this coil that I had laying around or just stick with OEM?

20240418_210122.jpg
 
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Now I think I'm getting it, thanks.

4. So, with the Sniper kit, the resistor is no longer needed. Does that mean I shouldn't have been using the resistor with the Mallory distributor? I ask because someone once asked me if I needed it and I didn't know how to answer, only that it's on there now so I assume it's needed (the car is just how I bought it). So the two wires from one side of the resistor will go together as mentioned and I will then delete the wire coming off the other side and going to wherever (I haven't traced it's destination, yet).

8. Yep. I have the OEM tach working. So leave the gray wire attached so the OEM tach works, then the (possible) yellow wire goes where the instructions say in order for the ECU to receive signal.

Okay, that's much better. Knowing it's okay to go to the battery side solves 75% of the issues I was having. In that case I can follow the instructions more closely. I was stuck with "well, this tells me to use the battery but I'm told not to, so now what?". LOL.

Awesome. Now I'm fired up and gonna go start on the car right now. Thank you, very much. I'll report back. And I wasn't kidding about the "nothing is free" thing. I'm more than willing to PayPal you something as a Technical Advisement fee :D
Good stuff!

#4
Actually, for that distributor you needed to have the ballast resistor. So, you were good there.

Do you have a test light and some form of volt/ammeter? Basically, check one of those wires at the resistor for power when the key is ON. Then, turn the key to START to see if it stays on. If it was powered in the ON position, it will likely not be during START. That's the ignition on circuit. The other wire will likely not power in the ON position, but will when the key is turned to START... that's the ignition start/crank circuit.

What I'm saying is the "simplest" method (because I don't know how other stuff is wired, etc.) is to connect both those wires to the ignition for the Sniper... that way when the key is ON it is getting power and when the key is at START it is also getting power. Of course, the resistor is no longer needed. Typically, the other wire will connect to the coil, but that's not always the case. This is where it get's tricky for me because some of the pics you sent... the wiring looks, well, not good. So, it's honestly hard to tell what your specific situation is.

At the end of the day, unplug all the wires from the resistor... stuff a test light into one, turn the key to ON and then to START and see which position lights up, or it may not light at all. Mark it and then move to the next one - repeat for all three wires.

LOL! Yeah... for some reason it seems counterintuitive to connect to the battery directly because you think it can't handle it... well it can.. and it needs to!

Please do report back.. I'm super curious!

I'm not going to take your money... that's nuts. If you feel compelled, donate a few bucks to a charity. I support the Special Operation Foundation (sfo.org), Green Beret Foundation (Green Beret Foundation - Supporting America’s Special Forces Soldiers and their families) and the Wounded Warrior Project (Veterans Charity - Non Profit Organization for Veterans | WWP).
 
Update: so, this isn't looking too bad. Since I don't have to worry about the power and ground, I am mounting the PDM over on the firewall where the resistor was.
And then brought the wiring harness from the EFI to that side which is good because that's where my coil is to run the yellow wire, power, ground everything. Right in one spot for the most part.
I'm finding that the PDM is not necessary, but I like the idea of it working as relays for everything, basically. I.E. power and ground is already there for fuel pump, switched source, fires up the fuel pump, etc. I like it. I had a switch wired to the interior the car for the fuel pump. It triggered a relay and the engine bay that fit power to it. Was nice to get rid of all that.
Having LEDs to monitor operating conditions and fault is kind of nice too.

I'll do some more work on it tomorrow. Should have all the wiring done.

Now that the resistor is gone, does anybody know how that affects my distributor?

Also, I am told to run the two power wires (blue and brown) from the resistor to the pink wire on my EFI harness, but what about the leftover resistor wire? The one from the other side. I believe it's black. Do I just leave it unplugged?
And does all of that mean that I should not have been running the resistor with my distributor? Mallory Unilite.
**EDIT** My instructions say that my distributor definitely needs the resistor. So do I just run a wire off of the side of the resistor with the two wires?.


View attachment 1649096

Lastly, now that the resistor is gone, can I use this coil that I had laying around or just stick with OEM?

View attachment 1649097
Take a look at these install instructions for your distributor.



1713527320017.png

Figure #1 is basically, your current setup.

If you look at the Sniper 2 install instructions, you are essentially doing what is on page 18.

1713527400894.png



The point I'm trying to make is your distributor should have been connected to the upstream side (full voltage) of the resistor. Meaning the distributor is operating with 12v. Keep in mind that the resistor - in this case - is designed for the coil and points distributors. In your case.. the coil will need the resistor. Some coils will come with resistors built in. I'm fairly certain that the Accel coil needs a resistor for the signal to the negative terminal. It will run fine with 12v... but in time that will take a toll on the coil and eventually start to cause issues.

Here is what I would do... Connect the yellow wire to the neg terminal on the coil. That way it will definitely work and things will run. If you have a meter, verify it's 12v. It's important to check this voltage. The Sniper MAY (unsure) be stepping it down to ~9v already, but I very much doubt that.

If it is at 12v, use the resistor you already have... move the yellow wire you connected to the coil from the ECU to one side of the resistor and then run a new wire from the other side of the resistor to the neg terminal on the coil. Check the voltage drop... you want it around 9v. If all good, you're set.

Keep in mind, dropping the voltage by using a resistor is to basically protect the coil. And that's one of the reasons you have two ignition wires... one 12v during start is to give the coil full power to ensure a start and a lower power circuit for just running so that the coil lasts longer.

Clear as mud? :)


BTW... this is why everything I own has electronic ignition... everything is 12v. I'm a fan of MSD boxes and I run the HyperSpark system on my main car. I have a MSD ready to run on another car with a Blaster 2 Red coil. Basically, spark and timing is critical. When that's not working well, nothing works well.
 
just in case you're curious... here is my 66 Charger's engine.

ignore the weird fuel line swinging over the side :) in the process of experimenting with flow. i jammed oversized injectors in the sniper... so it demands a lot of go juice.
1713529845261.png
 
Good stuff!

#4
Actually, for that distributor you needed to have the ballast resistor. So, you were good there.

Do you have a test light and some form of volt/ammeter? Basically, check one of those wires at the resistor for power when the key is ON. Then, turn the key to START to see if it stays on. If it was powered in the ON position, it will likely not be during START. That's the ignition on circuit. The other wire will likely not power in the ON position, but will when the key is turned to START... that's the ignition start/crank circuit.

What I'm saying is the "simplest" method (because I don't know how other stuff is wired, etc.) is to connect both those wires to the ignition for the Sniper... that way when the key is ON it is getting power and when the key is at START it is also getting power. Of course, the resistor is no longer needed. Typically, the other wire will connect to the coil, but that's not always the case. This is where it get's tricky for me because some of the pics you sent... the wiring looks, well, not good. So, it's honestly hard to tell what your specific situation is.

At the end of the day, unplug all the wires from the resistor... stuff a test light into one, turn the key to ON and then to START and see which position lights up, or it may not light at all. Mark it and then move to the next one - repeat for all three wires.

LOL! Yeah... for some reason it seems counterintuitive to connect to the battery directly because you think it can't handle it... well it can.. and it needs to!

Please do report back.. I'm super curious!

I'm not going to take your money... that's nuts. If you feel compelled, donate a few bucks to a charity. I support the Special Operation Foundation (sfo.org), Green Beret Foundation (Green Beret Foundation - Supporting America’s Special Forces Soldiers and their families) and the Wounded Warrior Project (Veterans Charity - Non Profit Organization for Veterans | WWP).

Take a look at these install instructions for your distributor.

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View attachment 1649175
Figure #1 is basically, your current setup.

If you look at the Sniper 2 install instructions, you are essentially doing what is on page 18.

View attachment 1649176


The point I'm trying to make is your distributor should have been connected to the upstream side (full voltage) of the resistor. Meaning the distributor is operating with 12v. Keep in mind that the resistor - in this case - is designed for the coil and points distributors. In your case.. the coil will need the resistor. Some coils will come with resistors built in. I'm fairly certain that the Accel coil needs a resistor for the signal to the negative terminal. It will run fine with 12v... but in time that will take a toll on the coil and eventually start to cause issues.

Here is what I would do... Connect the yellow wire to the neg terminal on the coil. That way it will definitely work and things will run. If you have a meter, verify it's 12v. It's important to check this voltage. The Sniper MAY (unsure) be stepping it down to ~9v already, but I very much doubt that.

If it is at 12v, use the resistor you already have... move the yellow wire you connected to the coil from the ECU to one side of the resistor and then run a new wire from the other side of the resistor to the neg terminal on the coil. Check the voltage drop... you want it around 9v. If all good, you're set.

Keep in mind, dropping the voltage by using a resistor is to basically protect the coil. And that's one of the reasons you have two ignition wires... one 12v during start is to give the coil full power to ensure a start and a lower power circuit for just running so that the coil lasts longer.

Clear as mud? :)


BTW... this is why everything I own has electronic ignition... everything is 12v. I'm a fan of MSD boxes and I run the HyperSpark system on my main car. I have a MSD ready to run on another car with a Blaster 2 Red coil. Basically, spark and timing is critical. When that's not working well, nothing works well.

Actually that all is *starting* to make sense, now that I'm understanding the functioning of these parts. Okay.. In the first picture, from unilite, I see where power goes through the resistor to save the coil. Got it.
It sounds like 12v power from ignition and the power wire to the distbutor both attach to the same side of the resistor. That way 12v goes directly to the dist and the coil side gets 9v or so after going through the resistor. So far so good?
I'm guessing those are the blue and brown wires on the one side (I have a FSM to verify, just "typing out loud" to think through it all and make conversation LOL). The single wire from the other side of the resistor must be going to the coil (-) post. Close?
...But then it sounds like one of those wires (blue and brown) are powered with key in "start" and the other in "on". So then seems I'd be looking for three wires (START power, ON power, and one going to dist) on one side and one (to coil) on the other.
In either case, I do have a volt meter so will test all of this as soon as I'm back in town.
Connect yellow wire to coil.. if over 9v, run though resistor in the same direction as igintion power. Check. The yellow wire is only for the Sniper to use as a source for RPM (tach), correct? I assume it needs to see 9v same as the coil, since they assume the coil will run at 9v.
On top of all this, am I ALSO wanting to use the resistor post that has the START and ON power to run the pink wire to the PDM so that it knows when to fire things up and start the fuel pump?
I sent $100 to The Wounded Warrior Project and promise to send another $100 once the car starts. Deal? :D
I'm headed out of country but will be back to working on the car starting April 30. I'm gonna be anxious to get back so I can play with the car again. I've been letting it sit due to being so intimidated by all of this. I didn't want to fry my wiring. LOL.
 
It's go time. I'm pretty good on everything but I'm still stuck on this source for 12 volts, switched.
I've got one post that tells me to take the blue and brown wires from the resistor and use one of them as the switched source, then delete the resistor. But then a couple posts later I'm being told I need to keep the resistor because I don't want to burn up my coil another electronics.
So I made a quick video. It's only a minute long if you want to look at it real fast.
I'm assuming I test both the blue and brown wires and tap into the one that is switched, not the constant power. Correct? Does anybody know which wire it is before I break the connector apart?


**Edit: according to my voltmeter and the factory service manual, it actually looks like power comes from the single wire, goes through the resistor, then out to the two wires on the other side. I thought it went the other direction. Now it makes more sense. I can tap into the single wire going into the resistor as my switched 12 volt source, yes?

 
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It's go time. I'm pretty good on everything but I'm still stuck on this source for 12 volts, switched.
I've got one post that tells me to take the blue and brown wires from the resistor and use one of them as the switched source, then delete the resistor. But then a couple posts later I'm being told I need to keep the resistor because I don't want to burn up my coil another electronics.
So I made a quick video. It's only a minute long if you want to look at it real fast.
I'm assuming I test both the blue and brown wires and tap into the one that is switched, not the constant power. Correct? Does anybody know which wire it is before I break the connector apart?


**Edit: according to my voltmeter and the factory service manual, it actually looks like power comes from the single wire, goes through the resistor, then out to the two wires on the other side. I thought it went the other direction. Now it makes more sense. I can tap into the single wire going into the resistor as my switched 12 volt source, yes?


Actually. you were more correct with your first understanding of blue and brown wires. The brown wire (145BR) comes from ignition switch in "START" position to feed full battery power to the coil. When you release the "Start" function then power comes to the ballast resistor via the blue (16DBL) wire then through the resistor a reduced voltage is passed to the coil. If you are running a stock ignition then applying full power during run mode will eventually burn up your coil. If you are running an altered ignition that will need to be considered.

Sorry I can't help beyond that. Don't know the Sniper demands.
 
Actually. you were more correct with your first understanding of blue and brown wires. The brown wire (145BR) comes from ignition switch in "START" position to feed full battery power to the coil. When you release the "Start" function then power comes to the ballast resistor via the blue (16DBL) wire then through the resistor a reduced voltage is passed to the coil. If you are running a stock ignition then applying full power during run mode will eventually burn up your coil. If you are running an altered ignition that will need to be considered.

Sorry I can't help beyond that. Don't know the Sniper demands.

Interesting. When I turn the key to "on", my voltmeter shows 11v on the single wire side and around 6v on the side with the blue and brown wires. That led me to believe power was coming from the single wire then going to the blue and brown.
Of course, that's with the key on, not while starting. I guess that changes things.
The EFI just needs a switched source so that it knows when to turn on the fuel pump so I can start the car. Sounds like the blue wire is the one I need...Since brown would only fire up the fuel pump while the keys in the start position.
Or I go back and use the relay and switch under the dash to manually turn on the fuel pump like I used to. Then no worries and I would somewhat have a kill switch.
 
Interesting. When I turn the key to "on", my voltmeter shows 11v on the single wire side and around 6v on the side with the blue and brown wires. That led me to believe power was coming from the single wire then going to the blue and brown.
Of course, that's with the key on, not while starting. I guess that changes things.
The EFI just needs a switched source so that it knows when to turn on the fuel pump so I can start the car. Sounds like the blue wire is the one I need...Since brown would only fire up the fuel pump while the keys in the start position.
Or I go back and use the relay and switch under the dash to manually turn on the fuel pump like I used to. Then no worries and I would somewhat have a kill switch.
I'm guessing the engineers didn't take into consideration our 50 year old technology. I seem to recall reading about guys using alternator output power (dirty power) instead of clean battery positive terminal power then having occasional issues. The down side to using the battery power is that your amp gauge will show a discharging condition until the rpms get high enough to overcome that Sniper current draw. That in itself is not a HUGE issue as long as you understand what is causing it and have boosted the wire harness/bulkhead connector current carrying ability. I'm sure you had seen several conversations about charge path and bulkhead connector improvements.

Here is a simple circuit that will let you take trigger voltage from the brown and blue wires to activate the relay direct from your ignition switch. The two steering diodes block current from unwanted locations. I did a google search for steering diode so you can find some. The silver band on the diode it the same as the vertical bar in the diode symbol.
View attachment 1657786

3 amp steering diode - Google Search
 
I'm guessing the engineers didn't take into consideration our 50 year old technology. I seem to recall reading about guys using alternator output power (dirty power) instead of clean battery positive terminal power then having occasional issues. The down side to using the battery power is that your amp gauge will show a discharging condition until the rpms get high enough to overcome that Sniper current draw. That in itself is not a HUGE issue as long as you understand what is causing it and have boosted the wire harness/bulkhead connector current carrying ability. I'm sure you had seen several conversations about charge path and bulkhead connector improvements.

Here is a simple circuit that will let you take trigger voltage from the brown and blue wires to activate the relay direct from your ignition switch. The two steering diodes block current from unwanted locations. I did a google search for steering diode so you can find some. The silver band on the diode it the same as the vertical bar in the diode symbol.
View attachment 1657786

3 amp steering diode - Google Search

I have sales conversations. So basically, I just want to run a wire from the positive terminal the battery to one side of the ammeter. Then I run another wire from the other side of the ammeter to the alternator. Is that about right? That way those wires take most of the load and the bulkhead doesn't suffer. If I'm understanding correctly.
I have no idea what diodes are or how they work, but thank you lol.
 
Let's start over. If I buy the distributor that goes with this ignition system, then I can delete the resistor.
Does that make any of this easier?
 
It is not the distributor that gets damaged. The coil gets too hot and cooks because the Ballast resistor is not there to reduce voltage/current flow to it. You would most likely need to replace your ignition system to match up things.

Disregard what I sent you about the simple circuit!! I had my head screwed on backward so it's NOT correct anyway. Just went out to my shop and mocked up the circuit. If you want to do this, send me a private conversation with your address and I'll send you the two diodes and a description how to connect them to the relay you have been using instead of the switch. Then you can use that relay to feed switched power to the Sniper as designed.
 
It is not the distributor that gets damaged. The coil gets too hot and cooks because the Ballast resistor is not there to reduce voltage/current flow to it. You would most likely need to replace your ignition system to match up things.

Disregard what I sent you about the simple circuit!! I had my head screwed on backward so it's NOT correct anyway. Just went out to my shop and mocked up the circuit. If you want to do this, send me a private conversation with your address and I'll send you the two diodes and a description how to connect them to the relay you have been using instead of the switch. Then you can use that relay to feed switched power to the Sniper as designed.

Deal! Thanks, sir.
 
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