Battery in Trunk Wiring That Exceeds NHRA Requirements

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Sweet... well done.

That 6ga should be fine for the alt line. If you have a bunch of stuff running up front, fans, electric pump, efi you may want to consider setting it up on relays up front or dragging power to relays from the alternator charge.
 
I've been watching as crackedback is a great source of knowledge and expertise on these systems. Hats off to success for another member!!

One thing that you two may have discussed and addressed is the battery charge wire coming from the alternator to the battery in the trunk. You've already done the good stuff of keeping the starter wire dead except during crank (I did that too) but when I wired mine, I was also nervous about the charging wire shorting on either end since it is hooked to the battery and hot all the time. I have a single wire alternator so mine has a 4ga charging wire from the alternator to the battery but I protected it on either end (Maxi-fuses) in case of a short. Thought of fusible links but figured a Maxi-Fuse would be easier to change if it blows.
My $.02...
 
Demonx2 said:
I've been watching as crackedback is a great source of knowledge and expertise on these systems. Hats off to success for another member!!

One thing that you two may have discussed and addressed is the battery charge wire coming from the alternator to the battery in the trunk. You've already done the good stuff of keeping the starter wire dead except during crank (I did that too) but when I wired mine, I was also nervous about the charging wire shorting on either end since it is hooked to the battery and hot all the time. I have a single wire alternator so mine has a 4ga charging wire from the alternator to the battery but I protected it on either end (Maxi-fuses) in case of a short. Thought of fusible links but figured a Maxi-Fuse would be easier to change if it blows.
My $.02...
Click to expand...
Thanks.
Yes, I plan on a maxi link in the charge wire. Maybe 2 now...
 
crackedback said:
Sweet... well done.

That 6ga should be fine for the alt line. If you have a bunch of stuff running up front, fans, electric pump, efi you may want to consider setting it up on relays up front or dragging power to relays from the alternator charge.
Click to expand...
The biggest draw is a 5 amp fuel pump (Holley Blue).
 
Not to hy-jack but what fuse and holders are you guys using for 4 Ga. wire Alt. wire or is that overkill ?
 
My main and starter cables are 1/0, the power feed wire to the front and the charge wire from the alternator are #4. My charge wire is only hot if the key is on, and of course the MD. As I mentioned in my previous post, when the MD is off, nothing on the car side of it is hot.

crackedback is a good guy and helped a lot of people. If you ever need good relays he can fix you up. :thumbsup:
 
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I have a 95-amp alternator and a 4ga charging wire. So I use a 150a fuse on each end to protect for a short to ground. My overall wiring is similar but not exact to crackedback's as I had designed it prior to seeing his. Also my fuse panel locations and feeds prompted differences.
 
upload_2022-9-14_14-23-47.jpeg

I added some notes to crackedback’s schematic to reflect how I did this.
“From a dummies standpoint”. :lol:
 
mopowers said:
I'm getting ready to go through all of this myself on my 66. Where'd you end up purchasing your supplies (cable, terminals, etc)?
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I got the cable and copper lugs here: www.wireandsupply.com I guess they would be okay for the 14 gauge and crimp connectors, but I got them from Amazon before I came across Wire and Supply.
One thing about the 14 gauge copper; if it's cheap, read closer, it's probably copper clad aluminum.
I probably got the shrink tubing from Amazon, too. It's been a while.
 
SpeedThrills said:
I'm going to use this on my 6 gauge. I've used this type on my pick up truck's brake controller and winch. No spares to carry.
https://www.amazon.com/gp/product/B08RX5QN4P/?tag=fabo03-20
Click to expand...

Mount that circuit breaker on the side of your battery box, clip the cable headed to the cut off switch and put a couple ends on. Looks like you have enough cable to get that done.
@SpeedThrills
Be careful with what you buy for the amp rating on those breakers. That says it's 12-48VDC. 12 volts and 60 amps is MUCH different energy than 48 volts and 60 amps. Make sure you size the breaker to the 12 volt rating as the 60 unit will not likely ever trip unless you started welding with your 1/0 cable up front. IIRC some of those 60 amp breakers are at 200+ amps on a 12 volt system.

Appreciate the positive feedback from folks regarding my approach and help. Thanks!
 
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upload_2022-9-20_17-31-42.jpeg

Final pic, showing the 60a breaker
in the alt. charge wire. Tidyed it all up with some split wire loom wrap.

I also put a 15a fuse each, in the switched power source wire, and the wire that goes to the middle of the factory starter relay (with the square retainer on it, don’t know what it’s called).
That leaves the 1/0 ga. cable from the cut off switch to the top of the factory starter relay. @crackedback, how many amps does that breaker need to be? I have a mini starter for a mid 90’s Dakota. I can only guess that it would be an educated guess, as the draw would be different depending on heat, compression, starter efficiency, etc.
 
SpeedThrills said:
View attachment 1715988433
Final pic, showing the 60a breaker
in the alt. charge wire. Tidyed it all up with some split wire loom wrap.
That leaves the 1/0 ga. cable from the cut off switch to the top of the factory starter relay. @crackedback, how many amps does that breaker need to be? I have a mini starter for a mid 90’s Dakota. I can only guess that it would be an educated guess, as the draw would be different depending on heat, compression, starter efficiency, etc.
Click to expand...

"I also put a 15a fuse each, in the switched power source wire, and the wire that goes to the middle of the factory starter relay (with the square retainer on it, don’t know what it’s called)."

WHY, on the ford relay? It's only on when you crank the engine, totally unnecessary.

The trigger wire to the CD relay is OK to have a fuse in it

Cable from the left side of your ford starter relay to the cutoff switch in your tail panel is the one that needs a breaker or fuse. That is the one that I suggested the breaker be installed on,
NOT the cable from the alternator, although you can certainly fuse it if you like.

Your starter relay up front is ONLY a buspoint. Look at the SCHEMATIC!!!! That 1/0 off your cutoff switch does NOTHING regarding the starter. NOTHING! Power for the starter is provided from cable on the right side of ford relay. I usually run a maxi fuse that pops at 40-60 amps on a 12v system on that line depending on expected loads.
 
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EDIT: I didn't post this correctly, but my questions are both inside and outside the quote.
I'm glad I posted again because crackedback pointed out that I still don't know what I'm doing!
I'm getting closer, and as I said before, I'm glad to keep asking questions as long as crackedback doesn't mind answering them and correcting me.
I learned years ago, that if you can explain a given subject to someone else, you know it. I'm not there, and don't expect to be without electrical training, but that, I think, is helping me ask more pointed questions.

crackedback said:
"I also put a 15a fuse each, in the switched power source wire, and the wire that goes to the middle of the factory starter relay (with the square retainer on it, don’t know what it’s called)."

WHY, on the ford relay? It's only on when you crank the engine, totally unnecessary. Okay, but it's there now.

The trigger wire to the CD relay is OK to have a fuse in it. :thumbsup:

Cable from the left side of your ford starter relay to the cutoff switch in your tail panel is the one that needs a breaker or fuse. That is the one that I suggested the breaker be installed on,
NOT the cable from the alternator, although you can certainly fuse it if you like.
I forgot you suggested that. If I remove that breaker from the alt. cable, (this one) https://www.amazon.com/gp/product/B08RX5QN4P/?tag=fabo03-20 can I use it (is it the correct one) between the left side Ford solenoid and the cut off switch? You mentioned a rating being different because of the 12-48 volt rating of the breaker. I don't understand the theory there. I get that the 1/0 gauge from the Ford solenoid to the cutoff, and from the cutoff to the factory starter solenoid (now a bus), is too heavy (you did mention that). I'd like to replace that with something more appropriate. Would 6 ga. be adequate? I believe 10 ga. is factory, with a much shorter run.(Again, I don't know how to figure that.) I had been thinking that starter amperage went through that, thus the 1/0. It would also be easier to connect a lighter wire to a lug that would connect to the breaker, instead of 1/0 ga. to a relatively smaller breaker. (At least as far as my limited knowledge goes.)

Your starter relay up front is ONLY a buspoint. Look at the SCHEMATIC!!!! That 1/0 off your cutoff switch does NOTHING regarding the starter. NOTHING! Power for the starter is provided from cable on the right side of ford relay. I usually run a maxi fuse that pops at 40-60 amps on a 12v system on that line depending on expected loads.
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A 40-60 amp fuse on the starter cable, or the one going to the factory starter solenoid (middle connection)? Seems that the starter would draw more than that.
 
1Q3qink.jpg


The "S" cable going to starter on engine... nothing in this cable to protect it.

The cable with "SR" going to starter relay on your fender, needs some type of breaker or fuse in line. Either cable going to the cutoff switch can be fused. In or out, no biggie. This all goes back to what is the worst case deal. On this car, I put it in the line between the battery and cutoff switch...

gr5AxR8.jpg


WHY... Because the switch has a panel behind it. IF the car was to take a hit in rear and push the cutoff into that panel, dead short. Kill power with a fuse before cutoff, dead short, fuse pops, no danger.
 
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crackedback said:
"I also put a 15a fuse each, in the switched power source wire, and the wire that goes to the middle of the factory starter relay (with the square retainer on it, don’t know what it’s called)."

WHY, on the ford relay? It's only on when you crank the engine, totally unnecessary.

The trigger wire to the CD relay is OK to have a fuse in it

Cable from the left side of your ford starter relay to the cutoff switch in your tail panel is the one that needs a breaker or fuse. That is the one that I suggested the breaker be installed on,
NOT the cable from the alternator, although you can certainly fuse it if you like.

Your starter relay up front is ONLY a buspoint. Look at the SCHEMATIC!!!! That 1/0 off your cutoff switch does NOTHING regarding the starter. NOTHING! Power for the starter is provided from cable on the right side of ford relay. I usually run a maxi fuse that pops at 40-60 amps on a 12v system on that line depending on expected loads.
Click to expand...

I screwed up post #67. Here's what I was try to do:

I'm glad I posted again because crackedback pointed out that I still don't know what I'm doing!
I'm getting closer, and as I said before, I'm glad to keep asking questions as long as crackedback doesn't mind answering them and correcting me.
I learned years ago, that if you can explain a given subject to someone else, you know it. I'm not there, and don't expect to be without electrical training, but that, I think, is helping me ask more pointed questions.

Here goes; (gotta be a better way to do this)

-Okay about the fuse on the Ford relay, but it's there now.

-Okay on the trigger wire being fused.

-Regarding having a breaker in the cable between the Ford solenoid and the cut off switch:
I forgot you suggested that. If I remove that breaker from the alt. cable, (this is the one I used) https://www.amazon.com/gp/product/B08RX5QN4P/?tag=fabo03-20 can I use it (is it the correct one) between the left side Ford solenoid and the cut off switch? If not, what do I need? You mentioned a rating being different because of the 12-48 volt rating of the breaker. I don't understand the theory there. I get that the 1/0 gauge from the Ford solenoid to the cutoff, and from the cutoff to the factory starter solenoid (now a bus), is too heavy (you did mention that). I'd like to replace that with something more appropriate. Would 6 ga. be adequate? I believe 10 ga. is factory, with a much shorter run.(Again, I don't know how to figure that.) I had been thinking that starter amperage went through that, thus the 1/0. It would also be easier to connect a lighter wire to a lug that would connect to the breaker, instead of 1/0 ga. to a relatively smaller breaker. (At least as far as my limited knowledge goes.)

-This is confusing me:
"Power for the starter is provided from cable on the right side of ford relay. I usually run a maxi fuse that pops at 40-60 amps on a 12v system on that line depending on expected loads." I thought it would need a higher rating, thinking that the starter draws more than 40-60.

-I got it regarding the 1/0 going from the cut off to the factory starter relay (middle connection) having nothing to do with the starter. (And, if I'm correct, it will be protected by the breaker I put in the cable between the cut off and the left side of the Ford solenoid.)

That's it for this go-round!
 
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Read the WHOLE statement... and your question which got the response in the first place (starter draw)! Which cable is it in reference too? The sentences above it has something there as well which addresses your question. Look at the schematic.

Also addressed in post 68.

Does the right side of the ford relay connect anywhere to your cut off, NO! We are talking about the cutoff switch circuit. My comment about the starter was only to point out it doesn't have anything to do with the breaker.

SpeedThrills said:
I screwed up post #67. Here's what I was try to do:

I'm glad I posted again because crackedback pointed out that I still don't know what I'm doing!
I'm getting closer, and as I said before, I'm glad to keep asking questions as long as crackedback doesn't mind answering them and correcting me.
I learned years ago, that if you can explain a given subject to someone else, you know it. I'm not there, and don't expect to be without electrical training, but that, I think, is helping me ask more pointed questions.

Here goes; (gotta be a better way to do this)

-Okay about the fuse on the Ford relay, but it's there now.

-Okay on the trigger wire being fused.

-Regarding having a breaker in the cable between the Ford solenoid and the cut off switch:
I forgot you suggested that. If I remove that breaker from the alt. cable, (this is the one I used) https://www.amazon.com/gp/product/B08RX5QN4P/?tag=fabo03-20 can I use it (is it the correct one) between the left side Ford solenoid and the cut off switch? You mentioned a rating being different because of the 12-48 volt rating of the breaker. I don't understand the theory there. I get that the 1/0 gauge from the Ford solenoid to the cutoff, and from the cutoff to the factory starter solenoid (now a bus), is too heavy (you did mention that). I'd like to replace that with something more appropriate. Would 6 ga. be adequate? I believe 10 ga. is factory, with a much shorter run.(Again, I don't know how to figure that.) I had been thinking that starter amperage went through that, thus the 1/0. It would also be easier to connect a lighter wire to a lug that would connect to the breaker, instead of 1/0 ga. to a relatively smaller breaker. (At least as far as my limited knowledge goes.)

-This is confusing me:
"Power for the starter is provided from cable on the right side of ford relay. I usually run a maxi fuse that pops at 40-60 amps on a 12v system on that line depending on expected loads." I thought it would need a higher rating, thinking that the starter draws more than 40-60.

-I got it regarding the 1/0 going from the cut off to the factory starter relay (middle connection) having nothing to do with the starter. (And, if I'm correct, it will be protected by the breaker I put in the cable between the cut off and the left side of the Ford solenoid.)

That's it for this go-round!
Click to expand...

Call the manufacturer about the breaker and its use here. I don't use them.

I run 4-6Ga from cutoff to OEM starter relay depending on loads. The nice thing about those size wires, you can put a maxi fuse holder inline very easily.

Added where the maxi-fuse or breaker should go.

1WzTrQO.jpg
 
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This statement: "The "S" cable going to starter on engine... nothing in this cable to protect it." I didn't know if you meant there is nothing in my set-up, and there should be or, protection is not needed in this cable. If I understand correctly, there is no protection on the wire to the starter because it is only hot when using the starter, and I discuss the 40-60 maxi fuse in the next paragraph.

Using this chart, I'll replace the 1/0 from the large, left side terminal of the Ford solenoid to the cut off, and the 1/0 going from the cut off to the top of the factory starter relay with 6 ga. and a 40-60 amp maxi fuse that I'll put between the left side Ford solenoid and the cut off.
I'd actually prefer to use a breaker, but I don't understand the 12-48 volt rating thing that you mentioned. As to if the voltage range affects the amp rating? If 12 can handle 60 amps, 48 can handle only 15, from what I read. (Ohm's Law thing, I guess.) But I'll only have 12. How does the 12-48 volt range affect an application?
wire-gauge-chart.jpg
 
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About your breaker...

CALL THE MANUFACTURER!!!!

Changing to the 6ga with some type of protection from cutoff to OEM starter relay is fine.

Home run on cable to physical starter, no breaks in the cable. Correct in your assumption only hot with key in start.
 
crackedback said:
About your breaker...

CALL THE MANUFACTURER!!!!

Changing to the 6ga with some type of protection from cutoff to OEM starter relay is fine.

Home run on cable to physical starter, no breaks in the cable. Correct in your assumption only hot with key in start.
Click to expand...
About my breaker... OKAY, I'LL CALL THE MANUFACTURER!! :poke: (Ha, I'll bet we'd be a blast as neighbors!) I thought maybe I was onto something regarding the Ohm's law thing.

Sounds like... I'm almost afraid to say... I might have it!!!

I'll post again with results. Thanks again. :thankyou::thumbsup:
 
RustyRatRod said:
You'd have him in a straight jacket the first day. ;)
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LMAO.

No, it would have been done with layout the first day in about an hour or two!

What takes about 5-10 minutes to explain in person, takes a novel to get across on the internet. All good, just follow the schematic.... :)
 
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