Solenoid for Trunk Mounted battery

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road chicken
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Solenoid for Trunk Mounted battery

Post by road chicken » Sun Mar 30, 2014 12:45 pm

Any suggestions for a solenoid for a trunk mounted battery? I'm figuring an old ( gag) Ford style unit should work for switching the main power feed to the starter.
4th generation B bodys- there is no substitute.
68 383, Street Demon 750, RPM top end,484/284/108 poo poo cam "-5 spd 4:10 SG, 4whl disk, Helwig Anti-Sway, Poly bushings,Firm Feel Box, HD Linkage, 1" t-bars, 7 leafs Springs

dangina
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Re: Solenoid for Trunk Mounted battery

Post by dangina » Mon Mar 31, 2014 11:24 am

I've been working on a plan to run a battery to the trunk, as well as running the toyota denso alternator upgrade, I found this drawing and I've added to it:

Image
400 stroked to 470ci, 3:55 Eaton true trac, slightly upgraded suspension lol

BUILD THREAD!!!! http://www.protouringmopar.com/showthread.php?796-1971-Speedipus-Rex&highlight=speedipus

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road chicken
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Re: Solenoid for Trunk Mounted battery

Post by road chicken » Mon Mar 31, 2014 2:14 pm

I did a MAJOR rewiring of the charging circuit and power feeds last year. It was worth every bit of time and money as the car has none of the typical low lights, slow signals and blower motor issues it used to. No "popping"( voltage drop) in the stereo when the signals are activated and no alternator whine through the speakers. I did have to cut the "AMPS" gauge out of the circuit and wire in a volt meter to monitor the system. Which is fine since that Amp meter is the cause of most fires under the dash- especially with modified wiring. The last little bit is rewiring the headlamps to run through relays.

I will be putting the solenoid where the diagram has the "cutoff" switch, as I have a separate power-feed running to the starter relay, ( protected by fusible link)- basically take the #4 wire and run it directly to the Battery + with a f-link at the battery. My concern being: I do not want the starter power cable energized at any time except for starting. One thing in your diagram, that #10 wire from the alternator should have a fusible link. I have a 75 amp output alt and boosted the wire gauges throughout the system to minimize voltage drop under high loading.

The relay to power the voltage regulator / Alternator field is similar and works very well and hold the voltage at 12.8-13.5V with no problems under any load. Full light, blower ect at idle ( 750 rpm).

Alt to Stater relay- 6ga (10 ga fuselink)
Starter relay to battery ( power feed) 8 Ga- ( 12 ga Fuselink)

Thanks.
4th generation B bodys- there is no substitute.
68 383, Street Demon 750, RPM top end,484/284/108 poo poo cam "-5 spd 4:10 SG, 4whl disk, Helwig Anti-Sway, Poly bushings,Firm Feel Box, HD Linkage, 1" t-bars, 7 leafs Springs

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road chicken
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Re: Solenoid for Trunk Mounted battery

Post by road chicken » Mon Mar 31, 2014 4:56 pm

For those interested in the conversion, it can be found here :

http://www.madelectrical.com/electrical ... uges.shtml

This site has some very good wiring mods and upgrade ideas. He makes it so even if you don't have a ton of electrical experience it is well laid out and explained.

AND... if anyone is thinking about buying a mopar alternator converted to one wire, I would highly advise against it. All they do is add a regulator to the back of the alt. This has two problems:

1) the regulator is cheap and will fail fairly quickly.
2) it does not sense the voltage accurately. it is too far away from the power distribution point ( Starter relay stud) and will cause issues while running and battery charge level.

By the regular 2-3 wire alternator,( amp output of choice) and add a ignition switched relay that connects the starter relay stud to the voltage regulator. It's called Remote Sensing and works light years better and more reliable than a one wire set up.
4th generation B bodys- there is no substitute.
68 383, Street Demon 750, RPM top end,484/284/108 poo poo cam "-5 spd 4:10 SG, 4whl disk, Helwig Anti-Sway, Poly bushings,Firm Feel Box, HD Linkage, 1" t-bars, 7 leafs Springs

dangina
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Posts: 394
Joined: Sat Feb 12, 2011 12:28 am
My Cars: 71 roadrunner
Location: lethbridge, ab

Re: Solenoid for Trunk Mounted battery

Post by dangina » Mon Mar 31, 2014 7:48 pm

road chicken wrote:I did a MAJOR rewiring of the charging circuit and power feeds last year. It was worth every bit of time and money as the car has none of the typical low lights, slow signals and blower motor issues it used to. No "popping"( voltage drop) in the stereo when the signals are activated and no alternator whine through the speakers. I did have to cut the "AMPS" gauge out of the circuit and wire in a volt meter to monitor the system. Which is fine since that Amp meter is the cause of most fires under the dash- especially with modified wiring. The last little bit is rewiring the headlamps to run through relays.

I will be putting the solenoid where the diagram has the "cutoff" switch, as I have a separate power-feed running to the starter relay, ( protected by fusible link)- basically take the #4 wire and run it directly to the Battery + with a f-link at the battery. My concern being: I do not want the starter power cable energized at any time except for starting. One thing in your diagram, that #10 wire from the alternator should have a fusible link. I have a 75 amp output alt and boosted the wire gauges throughout the system to minimize voltage drop under high loading.

The relay to power the voltage regulator / Alternator field is similar and works very well and hold the voltage at 12.8-13.5V with no problems under any load. Full light, blower ect at idle ( 750 rpm).

Alt to Stater relay- 6ga (10 ga fuselink)
Starter relay to battery ( power feed) 8 Ga- ( 12 ga Fuselink)

Thanks.
I wasn't sure what wire size for the #10 alternator to the starter relay, is #10 big enough? was thinking about maybe #8. I was going to add fuses in the diagram but I haven't yet.
I would like to also know how to wire up battery to starter in some way that its only "live" during starting and dead the rest of the time. I've been asking on other forums but most agree to this drawing so far. I just added the toyota alternator in there so I had a colored reference when I go to do this.
I've read about adding in a ford solenoid to do this but no good drawing on how to do this properly.

I was also going to put the red and black ammeter wire that goes through the bulkhead on a seperate bulkhead post to avoid the whole fire issue. I was actually thinking of cutting out the red and black wire and just running one bigger wire like a #6 to the spliced joint on the dash harness that feeds everything else.

question do you have to use fuseable links? I like seeing my fuses for easy replacement.

do you have a diagram on how to wire the front headlights on relays? I haven't found out how to do that yet
400 stroked to 470ci, 3:55 Eaton true trac, slightly upgraded suspension lol

BUILD THREAD!!!! http://www.protouringmopar.com/showthread.php?796-1971-Speedipus-Rex&highlight=speedipus

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road chicken
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Re: Solenoid for Trunk Mounted battery

Post by road chicken » Tue Apr 01, 2014 6:10 pm

Give me a day or two. I am making a wiring diagram with all these mods in one place, including the stater solenoid issue to keep the starter power wire powered only when it needs to be and head lights. It will be specific to the 71 year and wire codes.

I would suggest looking over and reading the MAD electrical link items for a background on the how and why .

You can use fuses if you like- especially if it is inside the passenger compartment. I use fusible links in the engine compartment and trunk, but they make a hell of a mess when they blow. so no good in the passenger compartment.

I would wire in an 8ga from the Alt output to the factory stater relay and then back to the battery. The bigger wire allows less resistance which translates into less voltage drop. That means the system can charge the battery better and more accurately. I use the factory stater relay stud as the power distribution point and wire the voltage regulator to "sense" the voltage there.

The MAD electric diagram does bypass the firewall feed through, as it is a major source of problems both in and out- ( old wiring, corrosion, high current), same as the AMP gauge.

There are so many connections in a stock car that all add up to problems and I eliminated as many of those as I could. I also solder EVERY connection since just crimping is marginal and will get worse over time no matter how secure.
4th generation B bodys- there is no substitute.
68 383, Street Demon 750, RPM top end,484/284/108 poo poo cam "-5 spd 4:10 SG, 4whl disk, Helwig Anti-Sway, Poly bushings,Firm Feel Box, HD Linkage, 1" t-bars, 7 leafs Springs

dangina
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Joined: Sat Feb 12, 2011 12:28 am
My Cars: 71 roadrunner
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Re: Solenoid for Trunk Mounted battery

Post by dangina » Tue Apr 01, 2014 6:53 pm

that would be great! I look forward to seeing it. I actually have found this diagram that I added to it so the poster can update it and he ended up collaborating with another member and they came up with the drawing above, that I added to that I posted here.

this may or may not help you? he added in the ford solenoid.

Image
400 stroked to 470ci, 3:55 Eaton true trac, slightly upgraded suspension lol

BUILD THREAD!!!! http://www.protouringmopar.com/showthread.php?796-1971-Speedipus-Rex&highlight=speedipus

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road chicken
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Re: Solenoid for Trunk Mounted battery

Post by road chicken » Tue Apr 01, 2014 8:21 pm

I'll look. I don't have a need for a master switch, but I will "wire" one in because I know people use them. I like his "fuse". That symbol is actually for a diode :shock:
4th generation B bodys- there is no substitute.
68 383, Street Demon 750, RPM top end,484/284/108 poo poo cam "-5 spd 4:10 SG, 4whl disk, Helwig Anti-Sway, Poly bushings,Firm Feel Box, HD Linkage, 1" t-bars, 7 leafs Springs

dangina
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Re: Solenoid for Trunk Mounted battery

Post by dangina » Thu Apr 03, 2014 2:17 pm

road chicken wrote:I'll look. I don't have a need for a master switch, but I will "wire" one in because I know people use them. I like his "fuse". That symbol is actually for a diode :shock:
I was thinking a battery disconnect in the trunk would be good, I was planning on using an electric trunk release, that way if you kill your battery thieves can't start your car or get in the trunk with power off. that symbol is a diode and he put one in to dissipate any charge left on the system?
400 stroked to 470ci, 3:55 Eaton true trac, slightly upgraded suspension lol

BUILD THREAD!!!! http://www.protouringmopar.com/showthread.php?796-1971-Speedipus-Rex&highlight=speedipus

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road chicken
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Re: Solenoid for Trunk Mounted battery

Post by road chicken » Fri Apr 04, 2014 4:29 pm

just quick update: I got slammed this week so i only have the diagram roughed out on paper. I'll try and get it finished this weekend. Getting back to work comes first though. :)
4th generation B bodys- there is no substitute.
68 383, Street Demon 750, RPM top end,484/284/108 poo poo cam "-5 spd 4:10 SG, 4whl disk, Helwig Anti-Sway, Poly bushings,Firm Feel Box, HD Linkage, 1" t-bars, 7 leafs Springs

dangina
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Re: Solenoid for Trunk Mounted battery

Post by dangina » Sat Apr 05, 2014 3:04 am

sweet! can't wait :beer:
400 stroked to 470ci, 3:55 Eaton true trac, slightly upgraded suspension lol

BUILD THREAD!!!! http://www.protouringmopar.com/showthread.php?796-1971-Speedipus-Rex&highlight=speedipus

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Re: Solenoid for Trunk Mounted battery

Post by moparite » Sat Apr 05, 2014 12:19 pm

Forgive me if i missed something here but why do you want a solenoid to feed the starter from the truck? Why not just run a positive cable up to the starter relay? If you don't want battery voltage going to the starter you can wire in the ford style solenoid in tandem with the starter relay. To figure out what gauge wire to use you need to know the amp draw plus the length of the run. Just to add the issues with the amp gauge issues, You can still run the amp gauge and not have full load going to the wires/dash gauge. You can wire in a "shunt bar" . The shunt carries the load and you can run small wires to the gauge. The stock gauge will not work with a shunt and have to be replace but you can still have the amp gauge and not worry about the issues of the factory style set up.Image

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Re: Solenoid for Trunk Mounted battery

Post by road chicken » Tue Apr 08, 2014 2:52 am

Almost done- I swear :D I figured I would add the under-dash rewiring as well. Now if you have to keep the amp meter- the schematic will have to be changed and basically take out the remote sensing for the voltage regulator and the direct connection ( de ja vue ) from the alternator output to the starter relay. However- I can almost guarantee the battery will not charge and you will get stuck, in need of a jump except on long, non-stop hauls of 50 miles or more. With the battery in the trunk it is too far away , both in distance and electrical contacts, to be kept charged with the factory wiring setup. I tried it that way and it took me 6 months and 3 jump starts to figure it out. It would pop right over when the cables were attached with no waiting- that was the clue, ( for me). The choice came down to put the battery back up front or lose the AMP meter and upgrade the wiring. Using the one point ( starter relay) to feed, draw, and sense the power keeps the battery topped off like it should.

As Moparite pointed out, The shunted meter will certainly work, and was used on some later models, but will take some mod of the gauge itself.
4th generation B bodys- there is no substitute.
68 383, Street Demon 750, RPM top end,484/284/108 poo poo cam "-5 spd 4:10 SG, 4whl disk, Helwig Anti-Sway, Poly bushings,Firm Feel Box, HD Linkage, 1" t-bars, 7 leafs Springs

dangina
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Posts: 394
Joined: Sat Feb 12, 2011 12:28 am
My Cars: 71 roadrunner
Location: lethbridge, ab

Re: Solenoid for Trunk Mounted battery

Post by dangina » Wed Apr 09, 2014 5:52 am

I myself am ditching the ammeter, it caused nothing but problems, I'm also gonna have the battery in the back for better weight distribution as I'm building this car to handle. My biggest problems with mopars over the past 15 years I've owned them has been wiring issues. They left me stranded more times than I can count and it turns you off from driving them which shouldn't be the case. Thats why this car I'm building will have 100% new wiring, as well as eliminating problems like the ammeter, and even upgrading the alternator to the toyota denso unit so I can eliminate the voltage regulator (another pain from the past).
400 stroked to 470ci, 3:55 Eaton true trac, slightly upgraded suspension lol

BUILD THREAD!!!! http://www.protouringmopar.com/showthread.php?796-1971-Speedipus-Rex&highlight=speedipus

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road chicken
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Re: Solenoid for Trunk Mounted battery

Post by road chicken » Wed Apr 09, 2014 7:45 pm

Same here. I want to go 500 -1000 mile weekends without thinking twice about it. I can almost guarantee the mopar Alt and Voltage regulator are not the problem. It's the wiring and all the fricking connections . Since I have redone mine, ( the way I will show in the diagram) it has worked great. Not one little hiccup with the electrical system. I will try and finish it up tonight. But I am working on the chicken as well. New top end and cam going in.
4th generation B bodys- there is no substitute.
68 383, Street Demon 750, RPM top end,484/284/108 poo poo cam "-5 spd 4:10 SG, 4whl disk, Helwig Anti-Sway, Poly bushings,Firm Feel Box, HD Linkage, 1" t-bars, 7 leafs Springs

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