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Battery relocation [Merged 3-8]

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Just to make sure, is this how it goes:
Starting from rear of car/pwr source.
Battery Positive > 150amp breaker > kill switch > to distribution block in engine compartment > starter wire and the 2/4 wires from fuse box.
Also, the wire/cable for the kill switch and breaker need to be the same? 1/0 gauge or 2 gauge, if you are using 2 gauge.
Thx
 
Just to make sure, is this how it goes:
Starting from rear of car/pwr source.
Battery Positive > 150amp breaker > kill switch > to distribution block in engine compartment > starter wire and the 2/4 wires from fuse box.
Also, the wire/cable for the kill switch and breaker need to be the same? 1/0 gauge or 2 gauge, if you are using 2 gauge.
Thx

If you mean for this to pass tech, and this switch has a single set of contacts, you need the alternator charging wire to attach to the kill switch on the same side as the battery feed. In other words, battery and alternator on one side of the switch, everything else on the other side.
 
Oh yeah, forgot about the alternator. I have the Moroso kill switch. So, it has 2 contact points.
Would I use 0 gauge for the kill switch too? I know the alternator could use 8 gauge, right?
 
If two contact points means two sets of contacts, use one to interupt the fuel pump and you don't have to worry about the alternator keeping the car running, just connect it to the starter if it's relocated or to your distribution block/etc.

The kill switch is on the main feed, so that should be at least 2 ga. The alternator charge wire carries up to about 75 amps, so depending on it's length, it should be "big." 8ga will work if it stays within the engine bay. If you have to run it all the way back to the switch I'd go bigger. In my case I ran it to the starter, which has the 1ga wire from the bat, then ran a 4ga wire from the other side of the switch to my distribution block. Again, if you have a second set of contacts to cut the pump you don't have to worry about any of this, so you can see why a switch with dual contacts makes life so much easier.
 
I'm putting in an upgraded 160A alternator and currently have a rear mounted battery w/cutoff.

Would it be ok to run both the OEM Alternator charging lines (light green+red) to the OEM location/80A fuse and a separate fused charging line (dark green) to the cutoff switch? Figure in this orientation:
1.) Both the the front (ignition) and rear (fuel pumps) of the car gets Alt power equally
2.) Can run a smaller gauge wire for rear run as would split duty with OEM lines
3.) Can pull the OEM 80A Alt fuse to pass NHRA inspection on cutoff swich (e.g. rear Alt Run would then carry full load).

BTW, what gauge would be ok for the hatch run?
 

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Execution is 90% of an effective battery relocation but I thought I'd draw up a quick block diagram so I know what I'm getting myself into. I'll be sure to create a Tech Article after I do this since our VFAQ lacks a battery relocation write-up. Theres more then one way to skin a cat, or re-wire/relocate the battery, I just want to know if I'm missing something here or is it this simple?

I'll be using Erics post from his fusebox relocation build log to help. turbosax battery relocation
Thanks for the input.

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:dsm:
 
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Execution is 90% of an effective battery relocation but I thought I'd draw up a quick block diagram so I know what I'm getting myself into. I'll be sure to create a Tech Article after I do this since our VFAQ lacks a battery relocation write-up. Theres more then one way to skin a cat, or re-wire/relocate the battery, I just want to know if I'm missing something here or is it this simple?

I'll be using Erics post from his fusebox relocation build log to help. turbosax battery relocation
Thanks for the input.

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:dsm:

I know that this thread is sort of old but I have to admit that having a diagram as you created makes the process seem very possible.
 
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It's that simple Corey (at least on paper) :thumb: Your diagram looks good to me, and almost exactly the same as the one we made for Eric's setup. Only thing I have is you'd have to see if a 1ga ground off the starter is necessary or even possible. Big wire isn't that easy to bend/manipulate, which is why we went with 4ga. But that's up to you.
 
I saw Erics pictures and that 1ga. didn't look like fun but I was thinking about using the KCA Kable and soldering everything with a torch. I know the specs are a bit different on the wiring itself but at 20ft the more flexible wire can still support 250A MAX load which is still more than enough for 90A alternator duties.

I'm going to run new ECU sensor grounds with 1ga. LOL JUST KIDDING!

:dsm:
 
My car is currently down but I want this battery relocation to be as hack free as possible. I'm going to try to get everything mounted/wired into place without actually moving the battery to the back until its completed, that way the car remains a DD and I'm not rushed. Heres one last final drawing I did (thanks Eric for giving me mounting ideas) so I know where everything's going.

Before I go any further I'd like to thank Eric (turbosax2) for the HUGE amount of help he gave me compiling this list and helping me understand what needed to be done.

Heres what the shopping list looks like so far:
I think its safe to say that doing a battery relocation the right way, using the parts listed above, budget for about $550 to do the relocation which doesn't include the cost of the battery.

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:dsm:
 
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Corey, I can send you a couple of the grommets from Mcmaster so you don't have to buy a pack of 25. PM your address and I'll get them out to you.
 
Where are you going to mount the power distribution? Near the kick panel?
I don't have my heater core/a/c unit/blower under the dash so I'm mounting it on the firewall under the dash.

:dsm:
 
I havent read every single page, but I did review a few of these diagrams.

Some have mentioned wiring the alternator to the kill switch, but haven't been too specific about the install.

Let's discuss the proper way to cut power to the alternator. I have a theory, but maybe I am wrong. Lets keep this technical.

I have been looking at several types of kill switches. Not all of them offer a provision for alternator protection. Don't you think that the alternator needs to go to ground when the switch is off and not just be turned off abruptly?

Take a look at this switch.

Pegasus - Master Battery Cutoff Switch with Alternator Protection

I also have to comment on the 1/0 gauge wiring. Its just way too overkill. 4ga wiring is rated for something around continuous 135A. Unless you're running a big sound system and a 200A alternator, 4ga for the battery and alternator will work just as good. Its also cheaper. All this fancy cabling is just expensive. Go to a welding supply store and get some wire. Its more pliable and bends easier. Not to mention, a fraction of the cost.

Here is a chart with some information regarding wire gauge.

American Wire Gauge table and AWG Electrical Current Load Limits with skin depth frequencies
 

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The alternator is grounded to the engine, through its case, so adding additional grounds to it won't do anything. Just making sure you've got solid grounds coming off the starter and negative battery terminal is crucial.

Here's the info/specs on the 1/0 power wire I plan to run, I have it linked to in post #409 but heres is a link to it as well. ---> Knukonceptz product detail for KCA KABLE 1/0 ULTRA FLEKS RED CCA POWER / GROUND CABLE 50'

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You're correct, the 4ga. wire would probably be enough to support my 90A alternator but why stretch it? I could also upgrade to a Saturn alternator in the future without changing the re-wire.

:dsm:
 
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I think its safe to say that doing a battery relocation the right way, using the parts listed above, budget for about $550 to do the relocation which doesn't include the cost of the battery.

$550!?!?!

In my case I don't need a kill switch right away so is it possible/advisable to run this setup for a while (continue to daily drive) and integrate the killswitch later?

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Instead of springing for this all at once?

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Yes, you can do without the kill switch, no problem. But if you ever go to do any sanctioned racing, you'll fail.

I realize that NHRA certified tracks require the kill switch (it is discussed on pages 4&5 of this thread and other similar threads) and you need it if you want to race there.

I was just thinking that connecting it withouth the killswitch would be a good intermediate step and would let me (and others) do the battery relocation without spending all $550 at once. Allthough I'm not sure how much money it would save....
 
The kill switch (which is linked to with a cost as well as everything else) and the few lugs being eliminated from the relocation would drop the cost to about $475 - $500. Of course, thats only if you use MY shopping list of parts too as I'm sure you could get it to about $300 by getting smaller gauge wire/etc.

:dsm:
 
I havent read every single page, but I did review a few of these diagrams.

Some have mentioned wiring the alternator to the kill switch, but haven't been too specific about the install.

Let's discuss the proper way to cut power to the alternator. I have a theory, but maybe I am wrong. Lets keep this technical.

I have been looking at several types of kill switches. Not all of them offer a provision for alternator protection. Don't you think that the alternator needs to go to ground when the switch is off and not just be turned off abruptly?

Take a look at this switch.

Pegasus - Master Battery Cutoff Switch with Alternator Protection

I also have to comment on the 1/0 gauge wiring. Its just way too overkill. 4ga wiring is rated for something around continuous 135A. Unless you're running a big sound system and a 200A alternator, 4ga for the battery and alternator will work just as good. Its also cheaper. All this fancy cabling is just expensive. Go to a welding supply store and get some wire. Its more pliable and bends easier. Not to mention, a fraction of the cost.

Here is a chart with some information regarding wire gauge.

American Wire Gauge table and AWG Electrical Current Load Limits with skin depth frequencies

There isn't such a thing as overkill in terms of 1/0, personally, I wouldn't run it because its big. I ran 4awg and I really haven't been thrilled with it and will switch to 2awg. Race cars, like in Grand-Am they will run 2 1/0 positive leads from the battery. It is possible to have too small of wire, but there aren't going to be draw backs to running 1/0.
And for a cheap shut down relay that will work, check out a Ford firewall mount starter relay, found for cheap at any auto parts store.
 
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