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Discussion Starter · #1 ·
I've searched but couldn't find info pertaining to my dilemma... Since I'm broke I figure this will kill some time and let me work on the car. And for the record, this car is EFI.

I want to move my solenoid to the trunk (Well, I don't 'want' to, but you guys have made me paranoid) but have a problem. Since this car is EFI, with a bunch of upgrades, I have about 8 things coming off the positive terminal of the solenoid up front. These include, main chassis harness (EZ-wiring kit.. 21 circuits, most only being used to trigger relays), main EFI harness (Must pull some amps I imagine.) and about 8 different relays or so (The 'direct from battery' feed, into the relay, if you know what I mean). These include electric fan, high beam and low beam, fuel pump, EFI ignition circuit (coil, module, etc), O2/MAF relay, and some other things i can't recall at this time).

What I'd like to do, is move the solenoid to the trunk, and run a 10 gauge cable up to the front (No bigger than 10 gauge, maybe 8 gauge, but I'm out of room), to a 'bus', or just really an isolated stud where the solenoid used to be. From there, I was going to attach everything again that used to be on the positive stud of the solenoid (Relays, chassis harness, efi harness), and a 130amp fused (150 amp fuse for some reason) alternator 4gauge wire. All those circuits are fused on their own of course, but all this would be redundant if I didn't fuse the 10 gauge cable running up the length of the car. If I didn't do that, obviously, I would have a non fused constant hot power source running up the side of the car, which of course, is what we are trying to avoid.

Now, my question on fusing the 10 gauge wire, is with all those 'direct from battery' relay wires, EFI harness, and chassis harness, and of course, giant alternator wire, the wire I run up front wll be carrying a substantial amount of amps. Maybe so much that I can't fuse it reliably near the battery with a fusible link or something? It would almost have to be another 125 amp fuse or something (Taking into account all the relays on at any given time, NOT even taking into account the alternator, which I'm not sure if I have to as it's fused beside the alternator, but since all it's charging will be going back to the battery, probably will need to take it into account, eh?). So with such a fuse of enormous proportions in the trunk, the wire will burn up before the fuse ever triggers, correct?

Making all this work, redundant and stupid?
If I have to run ALLLLLLL those wires to the trunk (Including the 4 gauge alternator wire, relay wires, etc) I'll just leave the solenoid up front.

I hope I explained that well, it's more easy to visualize in my head.

Thanks in advance!
 

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in my job, we fabricate trucks & run hot leads all over the place, inverters, generators & so forth, we just make certain the wire is run in a loom & whenever going through a metal body part, it is grommetted. we do not fuse the heavy battery lead so i would not worry about it in your case either.
 

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I'm assuming this is due to a trunk mounted battery? If that's the case, I remember a thread on this topic that someone had suggested using 2 solenoids. It seemed like the simplest and most effective solution IMO. 1 solenoid would be mounted by the battery and act soley as a relay. It would be wired to be energized in both the key on and start positions, sending power to the next solenoid through an appropriate gauge wire. The 2nd solenoid in the circuit would remain in the stock location and be wired normally except the main power cable would be coming from the 1st solenoid instead of directly from the battery. When the key is turned on everything is powered normally. When the key is off or if a collision severs any hot wire in the circuit the 1st solenoid would open, cutting power to the rest of car. The only down side to this arrangement I can think of is if anything needs a constant voltage source even when the key is off (like a clock, power door locks, or the memory lead from a radio) a power lead would have to be run to the trunk for it.
 

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Well, assuming he is using a mini starter he essentially will be running two solenoids. I would run a power wire up to the engine bay to a power junction block that is fused near the power source.

I'm in a similar situation. I already have my battery and solenoid mounted in the trunk and would like a power junction block (they were also used on Shelby cars, NPD Part number 14448-1 on page 131, but aftermarket ones are available as well). Instead of running a power wire from the trunk, would it be possible to run a wire from the alternator wire post to the junction block? There would still be the wire from this post going back to the solenoid in the trunk to charge the battery, but why not add another wire to the same alternator post and run it to the junction block? Random crap I've pondered about in the past but never put into action :lol:
 

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If I read that correctly and you plan on routing the alternator output to that terminal block and feeding the battery with a 10ga circuit, it's not going to work. 10ga wire will only handle about 40 amps, less if it is routed in a loom. The path from the alternator to the battery shouldn't be less than 4ga, maybe bigger based on distance.

If that's not what you meant, disregard. :loco:

Jay
 

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Discussion Starter · #7 ·
Well I'm using a regular starter with the solenoid on the fender.

That being said, the reason as I stated I'm hesitant about a power wire with it fused near the battery, is because that power wire (8 gauge?) is going to be supplying the load to the junction box, and that junction box as I said, is going to have EVERYTHING running from it. Chassis harness, EFI harness, and all the relays. As well, my 4 gauge wire from the alternator will be running to it.

Now my fear is that with every accessory and the EFI powered up (Electric fan, EFI, fuel pump, etc, etc), there is going to be a huge number of amps being drawn. Now my worry is this. Is most of it going to be coming through that long 8 gauge power wire? In which case I'm going to need a massive fuse near the battery.. When I'd like to use a clean fusible link or something. OR is most of these amps going to be drawn directly from the alternator, to the junction block? ANd the 8 gauge long power wire will only be used when the car is off and the alternator is not spinning?

I'm not sure if i'm explaining myself correctly here. But if I run a power wire to the rear, as stated, and I have a huge amp draw from all my accessories, I'm not sure if 8 guage is even enough, and I'm going to be using a huge fuse in the rear, and really, it's not much better than the current 1 gauge wire I have running from the battery, up to the solenoid in the engine compartment at the moment.. I mean, it would be more plausible to fuse, as it won't be running the starter, but it iwll be messy, require a 100 amp fuse or so, etc, etc..

But I'm wondering if it WON"T need to be huge, or require a 100 amp fuse, because most of the power will be going from the alternator, to the junction block, and to the accesorries/relays/harnesses. and NOT, like I fear, from the alternator, to the junction box, and THEN THROUGH the 8 gauge power wire to the battery.
 

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Discussion Starter · #8 ·
WholeNineYards said:
If I read that correctly and you plan on routing the alternator output to that terminal block and feeding the battery with a 10ga circuit, it's not going to work. 10ga wire will only handle about 40 amps, less if it is routed in a loom. The path from the alternator to the battery shouldn't be less than 4ga, maybe bigger based on distance.

If that's not what you meant, disregard. :loco:

Jay
That is sort of what I mean.

Then how do those who put the solenoid in the back accomplish this? Run a giant 4 gauge wire all through the car? Plus the wires that are normally on the + of the solenoid, PLUS a 1 gauge wire to the starter?

Whereas I'm wondering if most of the power will be straight from the alternator, to teh junction block, and then to the accessories.. And the 8gauge from the junction block to the battery wouldn't really have a high load on it, except either when the car is off, or when the battery is drained and the alternator is charging it.

(Maybe unrelated, but at the moment I have the alternator, with a 150amp maxi fuse and 4gauge cable going from the alternator, to the + of the solenoid up front).
 

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I was hoping someone would comment on my idea with the wire from the alternator to a power junction block in the engine bay. That would likely solve your problems and you wouldn't have to run a hot wire from the back of the car up to another solenoid or junction block.
 
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