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Battery relocation [Merged 3-8]

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I used the mister gasket kit ($99) from Jegs. Drill though the firewall behing the glove box (2g owners). Be sure to use plastic grommets when running the wire through the firewall also, this eliminates the posibility of grounding out the wire. I would also use a sealed battery such as an optima red top. I mounted mine in the spare tire well but I had to do some custom cutting.
 
I have my battery - Optima Red Top sealed in a Moroso battery box, relocated to the passanger side of the hatch area. Why do it? It offers better weight distribution, better handling, and frees up a lot or room under the hood. Plus your battery is sealed from the elements - which means no corrosion. I think it is a great and simple modification!!! :thumb:
 
I agree with all the benefits of relocating the battery...but let's not forget that placing the battery in the trunk means more wire between the battery and the starter, and more wire between the alternator and the battery...

more wire = greater voltage drops = harder starts in cold climate.
obviosly most people will not be affected unless they live in really cold places or they don't maintain their vehicles.

should also consider relocating the battery behind the passenger side
seat, for those of you who don't utilize the back seat of even have one.
(less wire)
 
Originally posted by Cesar
I agree with all the benefits of relocating the battery...but let's not forget that placing the battery in the trunk means more wire between the battery and the starter, and more wire between the alternator and the battery...

more wire = greater voltage drops = harder starts in cold climate.
obviosly most people will not be affected unless they live in really cold places or they don't maintain their vehicles.

should also consider relocating the battery behind the passenger side
seat, for those of you who don't utilize the back seat of even have one.
(less wire)


i TOTALLY agree, dont do it, its not worth it. i had mine back there for about a month, i'm an old fart and have been in car audio forever, the drop in refrence ground plays havoc with the ecu! grab a volt meter and cheeck before and after and youll see what i mean, your o2 will be of as well as the car will start a LOT slower, its not worth the trade off.

heres what i did, if you want to make more room and get a cleaner look.......

take out the charcoal canister, make a battery box and get a 98 CIVIC battery and drop it down by the TRANNY, it fits PERFECT! i can send you some pics of mine if you are interested.


JP
 
read your write up and it answered a lot of my questions, however, I have one more. What did you use to cover the stock + connections with your new wire? I know in the write up it says

"Now take the 3 stock wires which normally attach to the + battery terminal, put them all on top of eachother along with the new wire's connector and stick a bolt through the middle. Tighten it up with the correct size nut. Make sure you cover the new connection with something to keep it from grounding out to a metal piece in the engine bay, or you'll blow the circuit breaker very often"

But what exactly did you use to Cover the new connection. I know the obvious answer would be electrical tape however will that really be the best thing?
 
And finally cover your battery with an NHRA battery box (Moroso makes one) so your not breatheing in toxic fumes that a battery lets off and have the vent tube run outside to of the car to vent those fumes away from the passenger compartment.

Unless your using a gel cel battery like a Optima or his Westco battery, make sure you cover it up. It's dangerous to run a normal battery open inside the car like that. So keep the price of a new battery or a battery box in mind when planning this mod.

Also if you ever plan on going to the drag strip and your battery is re-located you MUST have a battery on/off switch on the back of your car somewhere. This is a concrete NHRA and IHRA rules, so make sure you find a good location for that piece as well. They do leak so it's not really a great idea for a street car that will see rain.

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All right, I'll clear a few things up here...

As far as drilling holes through the firewall... it's been 3 years since I did an install in a 1g, so another one of you guys will have to help him on this part.

On a 2g-turbo car, run these down the passenger side, and drill your holes low on the firewall. I can take pics of mine. Be very careful on this part because you have a large group of wires going through the firewall there, and you have brake lines on the other side of the firewall as well. Check, double check, and then have someone else check again for you.

On a 2gnt, I ran the 12v on the driver's side. You can drill through right where the clutch cable runs through. It’s never pretty, but it works. On the passenger side, you can drill through pretty easily if I remember correctly. This is where I ran the ground cable.

Pick up (2) 20' lengths of 4-ga cable from your local stereo shop. The better the cable you get, the higher strand count and better conductivity. Color is your choice; I used stinger and lightning audio (silver and blue respectively). Also pick up a 4 or 8 pack of 4 ga ring terminals from your local stereo shop. The crimp on kind... be sure you have the tools to properly crimp these suckers on. Pick up either a circuit breaker or an ANL style fuse holder with the biggest fuse they have. I used a 200amp in my last car. It’s your choice, but pick up some new battery terminals as well. Some nice gold plated ones with the ability to really clamp down on some 4 ga. And finally, pick up either a 2 or 4 fuse distribution block. Not all stores have a 2 fuse, so the 4 will work fine.

Run both the 4 ga leads along the side of the car, (or underneath if you know what you're doing) to the back of the vehicle.

Obviously double-check your cables running from the battery to the front of the car. Make sure there's no kinks or places where the cable's sheathing could be rubbed down and arc. Don’t hook the cables up to the battery until everything is all done.

Under the hood (we're assuming you've drilled, and have 3-6'+ of 4 ga wire under the hood now), take the ground cable, and run that directly to where the factor ground mounts to the starter. (You can trace the factory ground to make it easier) you can remove that factory ground. Make sure you crimp that ring terminal on there solid. Now, you probably have 2-5'+ of grounding cable left...you should. Now, make another grounding cable to run from the starter, to the firewall. I'm not sure what the 1g has, but the 2g has an exposed ground cable that was around 6" long and bolted to the battery terminal. Again, make sure those ring terminals are tight. Now, depending on how much cable you have left, you may need to buy more. By now, you know how to handle this stuff, and you're sufficient with crimping on the ends. Find every factory ground under the hood, and replace it with your own. Ya know those grounding kits that sell for $89 bucks... you're now making your own for a fraction of the cost.

Now for the 12v cable, once you have it through the firewall, you need to find a place to mount your 2 or 4 fuse distribution block. You’ll run the main lead into this block, and then run the lead from the starter, into one of the side ports of it, not through a fused end. If you can, replace that cable to the starter with your own 4 ga one with nice ends. But if you can't, that's okay. Now you've got probably 4 white wires and another black or red one that need to be hooked up. I just paired up the white ones and put 2 in each of the fused leads. I had 2 left after that, and used one for the fuel pump, and the last one was open. Just make sure you have them all hooked up somewhere on the fused side of that block. As far as fuse sizes. I just used 60's and never had a problem.

Now check all your connections... then check em again...

Now back at the battery, ground it directly to the battery, for the 12v side, use a circuit breaker or a big ANL style fuse holder with like a 200amp fuse, and mount that fuse as close to the 12v battery terminal as possible... I've seen what can happen when people don't do this part properly...

Make sure the battery is secure. Either make your own battery box, or buy one, just be sure it's secure and the battery cannot move around. I would highly suggest using a dry-cell battery for the project. Like an optima red top. Putting a lead-acid battery in the back means it must be in a sealed enclosure, and that enclosure must be vented to the exterior of the vehicle. Not a super-hard task, but just get a dry-cell and don't think about it. Regardless it's still a good idea to seal up that battery compartment and vent it to the outside.

Now for those of you with big stereos that think, hey now my amp's only like 2 feet from the battery, super... wrong... you now have more fun ahead of you. You can mount the amp back there and have it >2' from the battery, but you also have to run 12v, and ground leads directly from the battery to the radio in the front of the car... unless of course you like the sound of bees coming through your stereo in unison with your rpm needle. Running direct wires to your headunit will alleviate that wonderful thing we call ground loop noise. Also, be sure the radio isn't grounded or touching anything metal where it's mounted, or guess what, now your radio has become the path of least resistance for several of the little gadgets and gizmos under your dash...let there be noise! Like I said, a whole lot more fun for ya...

If I missed or overlooked anything, please PM me and I'll address your ?s individually or add to this post. I’m on my 5th bag of M&M’s this morning…

For those of you who want to argue that 4 ga is too small, I did it... with a yellowtop (not the greatest starting battery in case you didn't know) in 10 below, and it remote started every time. I don't know what a better test would be...
 
ill take one tmrw night.


JP :talon:
 
That sounds like a good idea.. What did you use for the tray?
 
I moved my battery to the trunk for a few reasons.
#1. More room in the engine bay
#2. better weight distribution and handling (getting closer to 50/50)
#3. Weight on the rear drive axle instead of the front
#4. installed a FMIC with short route piping. Battery wouldn't fit in the
engine bay anymore because I have to move the coolant overflow
and several other things.

Try and tell me it wasn't worth it. I dont have all the car audio crap (amps and subs) weighing down my car and steaing power. So a smaller battery will generate more power than a big battery which is located in the trunk huh?
 
i am wondering the same thing. i have a 4 gague wire running to my rear hatch, and would like to use that. i have talked to some people who have done a relocation and they said 4gague should be enough and alot of the relocation kits use 4gague. personaly i would like to use 2gague but 4 is what i have.

and yes you need a fuse or breaker. it isnt nesesary to function but if that wire were to ground out...

if any one knows what size fuse or breaker to use i would like to know. i would gues to use the same amprage as the main fuse, but i would like another opinion.
 
I'm currently running 4gauge(one strand) just to the pos. ground your battery in the back somewhere and dont forget to ground the two cables that use to connect up front
 
4gauge will be kind of iffy. If you are using 4 gauge wire do not excede a fuse or circuit breaker higher then 125 amps. 4 gauge wire at about 15 feet won't handle much more then 130 amps without burning up. I have a 125 (I think) circuit breaker on mine and if I crank my car over longer then about 5 seconds it will trip the breaker. The longer you crank your car over and if you do it back to back the more amperage will get pulled. I have 2 gauge wire though. 4 gauge should be fine though for the time being. Hey at least you will know when your starter is going out! :thumb:
 
hey everyone. . i know this might not be a performance question. . but what does everyone or anyone think about moving the battery to the trunk. . . .is it better.. .worst?. . .and i know i have other questions now but i cant fully think of what they are . . but if i could get some opinions that would be great. . thanks everyone
Peace
 
fwd cars want to keep as much weight over the front wheels as possible. I guess my question would be WHY? move it to the trunk. Then you have to run heavy gauge wire up to the engine compartment.
 
Blk_99gst said:
fwd cars want to keep as much weight over the front wheels as possible. I guess my question would be WHY? move it to the trunk. Then you have to run heavy gauge wire up to the engine compartment.

yea. .thats. true. .i guesss moving it to the back is for looks. . and if u run out of room in the engine bay. . my current car is a 91 eclipse gs-t and the one in my gallery was my old car. . sohc 1.8 ltr sloowwww. . haha
 
I pull my motor tranny almost monthly these days. I tossed the battery in the back to make it easier to work on the car. Motor/tranny come out in ~3 hours if I'm motivated. Also makes room for my 3.5" UICP ;) Plenty of good reasons to do it, but if you dont have to its not worth the effort, and all the hoops you have to jump through to pass tech at the track.
 
anybody know where they sell any kits to relocate the bettery to the rear......
 
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