OK…
I just did a battery relocation to the trunk and thought i’d write an article on it because the teg tips, to me, was a bit unclear.
What you need:
2 guage wire. atleast 18 feet.
2 battery terminals.
1 power distribution block with 2 gauge output.
1 120watt in-line breaker (optional).
3 ring terminal.
1 battery box.
Ok. For the 2 guage wire, go to home depot. I got mine (THHN stranded) for 75 cents/foot. That’s cheaper than you will find at any audio store.
The power distribution block will be very hard to find. Most stores only go up to 4 guage.
The first step is to route your wire.
If you look right behind your injectors and a little down you will see a hole in the firewall. Mine was empty so I used that. Inside the car, it comes in a little to the right and above your gas pedal. Push it through from the inside of your car and give it enough length so that it just reaches the battery.
Next, pull down your interior carpet. In the front where the passenger’s feet are, there is a plastic clip holding the carpet down. Yank on the carpet and it will pop right out. There is also one behind the center console. Next, remove the plastic cover where the passenger’s right foot would be. Then pull the long plastic piece inside your door jam where the carpet is held down. Also yank off the rear plastic trim in the backseat on the passenger side. It’s just held on with clips and pops right out.
What I found was that 2 guage wire is VERY hard to work with. When it bends, it keeps its shape, so it is hard to route through the car.
After coming through the fire wall, I routed it behind the center console and then behind some foam above the ECU. From there it runs along the door jam where the carpet ends. It then goes inside and behind that plastic trim and then into the trunk on the passenger side.
The next step is to cut off the excess wire in your trunk. Don’t throw it out. Splice the wire and attach a ring terminal to it. Attach that end to your breaker on the post labeled AUX. Put a ring terminal on the wire you just cut off and connect that to the post on the breaker labeled BATT.
Now would be a good time to attach your battery box to the floor of your trunk. I have a false floor that I made, so I connected it to that. I would assume you would have to drill holes into the frame of your car under the stock plastic trunk floor. Once you get your battery box fastened, figure out how long the wire you just attached to the BATT post on the breaker needs to be to reach the box without too much slack. Cut it appropriately and put a RED terminal on the end of the wire.
You can theoretically use any part of the frame for a ground. If you are looking down at the trunk, there are three plastic pieces making up the walls. One on each side and one in the center. Remove the center trim, and pull the passenger side trim back. Looking down, where your rear wall meets the floor, there is a big gold nut that i used to ground the batter down. Connect a ring terminal to the extra piece of wire you have, remove that big gold nut from the trunk, scrape all the paint around the bolt off, and connect your wire there. Fasten the nut on tight.
Connect a BLACK terminal to the other end of this wire.
Now go to engine bay.
Remove your battery terminals. First the POS then the NEG.
After doing this, remove the two bolts connected to the rods that are holding your battery down. Remove the battery and the black piece that held it down. There are about 5 big nuts that you have to take off if you want to remove the battery tray. Connected to the tray are 2 plastic wire connectors. Just yank them off. One of mine wouldn’t come off so I pried it off. It’s ok, It’s just a plastic piece on the end. Just be careful of the wires connected to them. Now you can remove the tray and the two rods.
Good luck taking off the stock negative wire. I couldn’t find the right size of the two bolts holding it down, so I just cut it off. Since your battery will be in the trunk, you won’t need it.
Now clip the POS terminal off of the stock power wire. You should have two wires left that are taped together and in a wire loom. One of them runs to the fuse box and one of them runs to the starter. Attach those two wires to your power distribution block by putting the spliced wire in the holes and tightening them down with an allen key. Attach your 2 guage power wire to this block as well.
Now all you have to do is put your battery in the box, connect the POS wire, then the NEG wire, and you should be good to go!
IM me if you have any questions. DiamanteMatto is my Instant Messenger name.
Good luck!
(1)2 guage wire —> around 8 bucks for 18 feet
(2)2 guage ring terminal —> 16 bucks (expensive)
(1)120amp circuit breaker —>45 bucks
(1)power distributor —>20 bucks
(1)2 guage ring terminal —>4 bucks (from a different store than the first one.)
so… around 100 bucks. you can cut this in half if you dont get the circuit breaker, but then you should put a fuse on the line IN THE TRUNK so that if there is a surge you don’t set your interior on fire. you could use an inline fuse, but if it blows you’ll have to search for a new one, possibly in the middle of the night in the middle of nowhere. with the circuit breaker, you only need to push the reset button. plus, if you’re working on your car and need to disconnect the battery, you can just hit the ‘test’ button to cut the juice from your battery. it’s worth the money if you ask me.
I used a 100 amp breaker because it was the closest i could find to 80. I would have used an ANL type fuse but I liked the idea of not having to replace it ever.
I used 4 gauge welding cable on mine. It’s like monster cable or any of that other amplifier wire, but better and cheaper. 4 gauge welding leads are good for a 275 amp stick welder at 40 feet than its good for my 80 amp starter at 18 feet
you fools, you are neglecting a major reason why the battery is under the hood in the first place, under extreme conditions standard batteries are made to vent poisonous fumes. no joke. When i relocated my battery i switched to a gel core battery that will not vent. (Optima Redtop) even in a battery box you are taking a risk unless you put a racing battery or similar type in the trunk.
I have put Optimas in the trunk of my 91 civic and my 91 integra, and both times i ran 2 ga. cable through the firewall, under the carpet, past the shifter and e-barke, up under the rear seat and over to the battery.
Sorry for the outburst, i just wanted to make sure you understand that moving a standard lead-acid battery inside the car can be more dangerous than it first seems.
Apparently i need to delve into this topic a little further.
to prevent overcharging of a battery it is designed to vent the overabundant hydrogen gas
hydrogen has a very low ignition energy
hydrogen that is allowed to expand rapidly from high pressure can self ignite
hydrogen burns with a nonluminous flame which can be invisible under bright light
hydrogen has the highest burning velocity of any gas
hydrogen is combustible from concentrations as great as 74.2% to as low as 4% by volume
So if you are wondering how it is possible for your interior to burst into flames now you know.
And this has happened MANY times in car racing simply by the failure of the voltage regulator. Nothing tells you when a voltage regulator fries other than your battery is dead due to overcharging, venting hydrogen, and losing the capacity to store energy in the gas it has lost.
Q.E.D.
An alternative would be to install a voltage gauge so you can see if you are overcharging your battery.
Or you can just roll with your windows down all the time i suppose.
I was going to relocate my battery to the trunk until my alternator started giving me problems several months ago. When it began overcharging my battery, the gas odor was unbearable. It made it hard to breath and also made my eyes burn-and this was with the battey still in the engine compartment and driving with the windows down. Imagine if it it was in my trunk! :surrend:…:wahmb:
Do you really want something that potentially volatile inside your car? Gel cell is definitely the way to go if you prefer the battery in your trunk!
“Please point me to a person who died as a result of a battery relocation.”
Racing Poverty, Obviously I didn’t die but it felt like The Reaper had one hand around my neck and was gouging me in the eyes with the other. I could hear the battery hissing before I even popped the hood. It looked like it was going to explode. There was so much gas coming out of it that I had to jump back from the car just to catch my breath!
Mine was an extreme case, I’m sure, but it would’nt have to get nearly that bad for one to feel the effects if the battery was in the trunk. As the battery warms(usually during agressive driving), it WILL slowly release small amounts of hydrogen gas.
You got fucked. It is highly unlikely. My exhaust pipe bottomed out and a whole opened up between my header and cat. Does this mean peopel shouldnt buy aftermarket headers because of the exhaust that filled my cabin for days?
If you do this properly and don’t dick around, you’ll be ok. I think it is mentioned several times that you dod everythign at your own risk. And todays batteries rarely have issues like that, if you dont’t want to do it, don’t. I have never seen someone develop a problem becuase of this and I hate it when posts like yours scare people off for no reason.
So peoples, if you dont want to suffocate and die, and then have your car catch fire, buy a fucking gel battery, or vent your shit.
If your header and cat opened up how would carbon monoxide fill your cabin?
And people that buy aftermarket headers and then lower the ish out of their car should KNOW HOW TO DRIVE A LOWERED CAR so that you don’t break you precious headers.
While it does say to use the teg tips at your own risk most people would still follow the step-by-steps and finish the project before they think about what could go wrong. Lets admit it, most of the people working on their cars don’t know as much as they think they do. Just because you can bolt on a set of headers doesn’t qualify you to do jack shit.
One last point is that ALL lead-acid batteries made after 1987 are required to vent hydrogen because this is the alternative to them blowing up… kind of a death with dignity thing for batteries.
For the cheap-Os out there you can get a battery box (as low as $8) and use rubber hosing coming out of the top of the box (hydrogen is lighter than air) through the plastic rear panel, through the rear vent housing, into the wheel well. If your car is moving then the air outside will be at a lower pressure than the air in your battery box and self ventilate.
Plus a battery box will hide the fact that you still have the stock battery!
I must thank you though RacingPoverty, for helping bring this topic to discussion. It would be nice if a MOD could add a little note that suggests you vent you box or get a gel battery.
