Battery in Trunk Wiring That Exceeds NHRA Requirements

SpeedThrills

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What does the single wire off the 1 wire alternator do? It charges the battery and runs the car. I have no idea why you would think that is a field wire... a 1 wire doesn't have a field wire.

The main alt charge cable runs to where you have that yellow wire. You use ALL the OEM stuff up front, EXCEPT the OEM black charge wire that hooks to alternator. That black wire powers the car and you need it disconnected to isolate the alternator and battery from the other side of the cut off switch.

Follow the schematic EXACTLY, it works.

You see my picture. The black wire from cd going to right is power to the cut off. The other black wire going forward hits the starter relay. That is the ONLY wires attached at the cutoff switch. I also have a 60 amp maxi fuse in line to the cutoff. No alternator or starter cables.

I don't think that wire is a field wire. I was just saying that I have a stock alt. (I think I got confused about the field wire because 67Dart273 and Mattax's diagram used it.)

Anyway, after I disconnect the yellow wire from the field wire, as I have it now, I connect it to the charge post of the alt., and leave the original disconnected.

I believe other than that, that's all I have wrong.
 

SpeedThrills

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your cables off the cut off are huge.
If that's my biggest problem, I'll take it!
They're 1/0. I guess the one that goes from the cut off to the factory starter relay could be smaller, but I didn't know. I have some 4 ga. If that's big enough, I could swap it to save some weight.
I should have some time to work on it tomorrow. I reeeeally appreciate your help.
Electric is my Achilles Heel, for sure.
 

crackedback

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Put a fuse in the line from ford relay to the cutoff or the line going forward. Just in case something goes wrong up front.

You already have the cables made up, I wouldn't bother making a set of 4ga to replace it. I always chuckle at guys that aren't index racing in eliminator classes complaining about the extra cable. It's under 5 pounds in most every case running things my way. Go on a diet if the 5 pounds is killing your car, and your health would likely be improved as a side benefit. :lol: One complainer was 300+ back years ago... ironically funny to me.

No sweat, just follow the schematic. You generally can't mix and match approaches on this stuff.
 
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SpeedThrills

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My electrical ignorance continues. I don't mind, though. Maybe this thread will help someone else.

I removed the yellow wire from the blue field wire (leaving the field connected), and also removed the factory charge wire from the alt. Then I connected the yellow wire to the charge post on the alt.

It starts, everything works (lights, horn, etc.), and everything shuts off with the cut off. However, the battery is not being charged.

The disconnected factory charge wire has power when the cutoff switch is "on", but not when it is "off". (key off)

Wud I do? And wud I do now? :(

EDIT: by the way, this is a 74 with seatbelt interlock and I’ve also done a Mad Electrical ammeter bypass, if that’s relevant.
 
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crackedback

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Is there anything attached to the side of the relay you took the yellow wire off of?

You need a DEDICATED cable from alternator charge stud to that side of the relay.

Take a fresh pic of what you have now.
 

SpeedThrills

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I've tried 3 times to repost the same picture, because nothing has changed in the back. (This computer is driving me nuts!) I did what I think you said to do:
-I removed the yellow wire from the blue field at the front. It was tapped into the blue field, which was still connected to the alt.
-I disconnected the factory charge wire from the alt.
-I connected the yellow wire to the alt charge stud. What you said about a dedicated charge cable to the alt charge stud JUST SANK IN! That yellow wire isn't heavy enough.
With all respect, I'm starting to think something is missing from your schematic, but I'm probably missing something. In your photo, there is a cable between the right side of the CD and the right side of the Ford sol. In your schematic, there is nothing there. Am I wrong?
As info: the blue wire goes to switched power source, and the black wire goes to the center of the factory starter relay (the original wire that was on the center stud went to the starter.)
Regarding the 1/0 cables that can't be readily seen in the photo:
-Far side ("ON") of the cut off goes to the left, large stud on the Ford sol.
-Near side ("OFF") of the cut off goes to the top stud on the Ford sol.
-The large, right side, Ford sol goes to the starter. (And I put a jumper across the two studs on the starter.)
p8qi1hx-jpg-jpg.jpg
 
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SpeedThrills

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This is the same picture (shown in next post, puter driving me crazy!!), because nothing has changed in the back. I did what I think you said to do:
-I removed the yellow wire from the blue field at the front. It was tapped into the blue field, which was still connected to the alt.
-I disconnected the factory charge wire from the alt.
-I connected the yellow wire to the alt charge stud. What you said about a dedicated charge cable to the alt charge stud JUST SANK IN! That yellow wire isn't heavy enough.
With all respect, I'm starting to think something is missing from your schematic. In your photo, there is a cable between the right side of the CD and the right side of the Ford sol. In your schematic, there is nothing there. Am I wrong?
As info (relating to my photo): the blue wire goes to switched power source, and the black wire goes to the center of the factory starter relay (the wire that was on the center stud went to the starter.)
Regarding the 1/0 cables that can't be readily seen in the photo:
-Far side of the cut off goes to the large, left side of the Ford sol.
-Near side of the cut off goes to the top stud on the factory starter relay.
-Large, right side of Ford sol goes to the starter.
p8qi1hx-jpg-jpg.jpg
 
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crackedback

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-I removed the yellow wire from the blue field at the front. It was tapped into the blue field, which was still connected to the alt.
-I disconnected the factory charge wire from the alt.
-I connected the yellow wire to the alt charge stud. What you said about a dedicated charge cable to the alt charge stud JUST SANK IN! That yellow wire isn't heavy enough.
With all respect, I'm starting to think something is missing from your schematic. In your photo, there is a cable between the right side of the CD and the right side of the Ford sol. In your schematic, there is nothing there. Am I wrong? Yes, you are wrong.

As info: the blue wire goes to switched power source, and the black wire goes to the center of the factory starter relay (the wire that was on the center stud went to the starter.)
Regarding the 1/0 cables that can't be readily seen in the photo:
-Far side of the cut off goes to the large, left side of the Ford sol.
-Near side of the cut off goes to the top stud on the factory starter relay.
-Large, right side of Ford sol goes to the starter.
View attachment 1715984828

There is a red line going to each side of the CD relay on the schematic. Clear as day
The relays don't care which side the cables from battery or alternator are connected.
My wires are just flipped to the other side.
My jump wire is on the right side, in the schematic it is on the left side and the alternator cable is right side.

mX9CQq7.jpg
 
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crackedback

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Another thing to consider. Is the cable you have that jumps from CD relay to ford relay smaller than your cable from battery to CD relay? If so, think about why that is a poor approach.
 

SpeedThrills

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The relays don't care which side the cables from battery or alternator are connected.
My wires are just flipped to the other side.
My jump wire is on the right side, in the schematic it is on the left side and the alternator cable is right side.
Okay. I was seeing the cables in your pic wrong. It looked like the jumpers went from the CD to the Ford sol on both sides. I see now that the left side cable is not going from the CD to the sol, it goes off behind it.

So my yellow wire is connected in the right places, but it's obviously too small. Why is it not hot (with key on)? With the key on, the right, small terminal on the CD is hot, but the right large terminal (where the yellow wire is) isn't.
The disconnected factory charge wire is hot, key on or off, as I suppose it should be.
 

crackedback

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I'm not reviewing where your sub wires are going as I don't recall for sure.. If that feeds some fusebox, then it should be on the downstream side of the cutoff.

OEM black charge wire will be hot when the cutoff is in ON position. It needs to be terminated/covered so it can't short out anywhere
 

SpeedThrills

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Doesn't feed the fusebox. (I added) Gets switched power from it.
Factory charge wire is as you said.
Hot-switch on
Dead- switch off
"So my yellow wire is connected in the right places, but it's obviously too small. Why is it not hot (with key on)? With the key on, the right, small terminal on the CD is hot, but the right large terminal (where the yellow wire is) isn't."
This is my concern. The yellow wire in my picture goes to the charge stud. It will be made bigger. But it is connected in the right places at both ends, but is not hot. That's why the battery isn't charging.
 

crackedback

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what are the two post sticking out the front of the CD relay? Is the relay internally grounded? Is that other stud a ground stud so it activates?
 

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what are the two post sticking out the front of the CD relay? Is the relay internally grounded? Is that other stud a ground stud so it activates?

I want to do similar on my car, just wondering what the purpose of the CD between the alternator and ford relay ? Why not just direct ?
 

crackedback

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I want to do similar on my car, just wondering what the purpose of the CD between the alternator and ford relay ? Why not just direct ?

Nothing hot forward of the battery box. Been covered a bunch in these threads over the many years on this site as to why. Car BBQ is one of them.
 

crackedback

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Those relays are definitely designed for different working environments
 

SpeedThrills

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Those relays are definitely designed for different working environments
Gotcha. However, it helped me understand the difference. I know when a solenoid needs replacing, but have never taken the time to learn about them. I think that’s the main reason I had such a hard time with this.
And I say “had”, because I HAVE SUCCESS! IT WORKS! You made me think (ouch!) about grounds. Turns out the right side small stud of the CD is a ground. I put a test lead on there to ground, and presto! BTW, the continuous duty solenoid that I used is a Cole Hersee 24059, if anyone else runs into this.
I replaced that small yellow wire with a 6 gauge, I had mentioned that it was a 4 gauge that I had laying around, but it is a 6.
This photo shows the new 6 gauge wire and the jumper ground wire. All I have to do is finish everything up!
Thank you, crackedback, I could’ve never done it without you!
upload_2022-9-13_16-17-52.jpeg
 
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