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D.I.Y. Full Size Battery in Hatch 2.0

20K views 26 replies 14 participants last post by  shoegazer 
#1 · (Edited)
So I know I have another thread on placing your battery in the trunk but it's outdated and since then I've had a very bad incident. The car had a grounding issue that in the end cause an electrical fire. Everything is ok and fixed now but I learned from this experience and I hope you all do as well.

For those of you who already have a battery in the trunk and say it's been running fine for years I hear you. Mine was too...but bam one day there she went. I went to start the car and nothing. I had power but she wouldn't start. Tried it several times till randomly as I cranked it over she started smoking out the hood.

**IF YOUR GROUND IS ONLY TO THE REAR CHASSIS PLEASE FOLLOW THE STEPS AND ADD A GROUND FROM BATTERY DIRECTLY TO ENGINE**

With that said I'll redo the full DIY since it is different.

I went with a full size dry cell battery in the trunk. I choose the passenger side this time to offset the weight of the driver (minor detail but still a thought in mind)

To do so I just bought a universal tray and built a bracket to make it all fit evenly.


The tray sat on a lip and wouldn't sit evenly and flat. So I bent over some steel and drilled through it.




Then I bolted it to the trunk


on the bottom I used long washers for plenty of support


This tray is going no where!

I ran my 1gauge wire down the passenger side. Making sure anywhere the cable could rub it is wrapped up safely.


I also used brackets to secure it in place. Don't want it moving on you


I removed the kick panel and placed my new distribution block. It's a rockford fosgate stereo splitter


installed my wiring


I used a 1 to 3 because (Starter, Alternator, EPS)

Then ran the power wires out to the accessories through here



under the fenders and then through the bumper one leading to starter one leading to alternator.
 
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#2 · (Edited)
Now the new important part!
I have TWO grounds... I'm using 2 gauge wire


1 goes to the back chassis the second runs down the driver side and bolted directly to the engine!


I placed it right on the transmission backside because I came out the firewall by the pedals


to protect from corrosion make sure to cover all your cable ends


I also have TWO grounds on the engine going to the front frame. Hard to see but one is next to the alternator and one is next to the starter.



In the back for the battery I also added a 100amp breaker no more than 12" from the battery. I just bolted it to the panel




It is tough to tell from the picture but I fried EVERY ground on my harnessess connected to the chassis when the fire happen. It was a back current in the system. I was told by the speed shop the issue was no ground directly to the engine where the most current is being drawn. You want that grounded to the battery not the chassis. So please take the extra $50 for more cable and run a ground directly from battery to engine. Save yourself from the headache I had. With the new ground the car starts faster, smoother, runs better and all my gauges work quicker and kpro reads better according to my tuner. Try it for yourself and see.
 
#5 ·
Looks good spaz. My only question would be regarding the "TWO grounds on the engine going to the front frame. Hard to see but one is next to the alternator and one is next to the starter."
How come you choose such a weak location of the lower rad support to ground the engine to? Why not use the main frame of the car, like where the stock battery tray bolts used to be?
 
#6 ·
The other that you can't see is to the frame. The one on the radiator support frame piece is there because the headlight harness ground is semi close to it so I figure it could help with that.
 
#7 · (Edited)
I was wondering if there is much of a point for me to do it as I have two grounds already.

I have one to the rear ground (tail light harness)



And a second to mid chassis (Hatch and wiper harness)



This it where the battery sits just for reference



You think I would need one? Is it the fact that the extra ground you did is directly to the engine that makes it optimal or is it simply just another ground? Also don't know how true it is but I recall reading somewhere that a ground point shouldn't be more then 24" away from the battery (This is probably if its the only ground, but I dunno) :run: Also where did you get the distributor you had in your first DIY (That shows voltage being pulled, and if I'm not mistaken has fuses in it aswell), I haven't had luck locally in Canada or even online.

P.S Apologies for the amazing photography and spotless car.:rolleyes:
 
#8 · (Edited)
Yes because you're missing the point of voltage resistance.

Voltage is all about resistance. You want your best ground to be at the point of most resistance and that is at the engine where the starter and alternator are pulling the most current. So you want your ground location on the engine block where all the power is being sent and pulled from. This will also physically ground your engine block versus grounding your chassis and then grounding engine to chassis. The factory battery has a ground straight from the battery to the engine for this reason.
 
#11 ·
Well I am happy i came across your new DIY. I followed ur first one, using a Odyssey ER25 aka PC680 and just extended my power cable off my oem one, with 2 gauge wire and added a 100 amp stereo breaker fuse 12" away from battery. Then grounded it to the main ground on the rear hatch. I am not happy with the setup up, because i can be left stranded very easy if i do not have my booster pack with me :fuu: The car dies very easy and takes so long to turn over sometimes. Also the fuse blows if the car tries to start for over 4-5 sec. Sometimes if i set up my booster pack at the battery it wont crank over and need to hook it up off the oem battery terminal connector and clamp the ground on the tranny bolt. It's a real fucking pita to be worrying about this shit all the time lol. So with that said i think i am pretty dam lucky, that what happen to Spaz didn't happen to me already, and i am going to fix this asap. I am so happy i came across this new DIY, otherwise who knows what could of happen? Thanks Spaz
 
#14 ·
What amps are the fuses in the distribution block?
 
#18 · (Edited)
I did a distribution block in addition to the circuit breaker since I tied in my EPS (60 amp), under hood fuse box (100 amp) and starter (250 amp) at the distribution block. Since they require all different amp fuses I figured it was better to be safe than sorry but a fused distribution block is not required.
 
#22 ·
I finished my battery relocation the other week and now all of a sudden my digital distribution block (Xscorpion DMANL3034P) is displaying a voltage of 0.00 V. I know this is incorrect as I have a digital display on my positive battery terminal which reads the correct voltage and everything is operating properly. Has anyone else encountered a problem like this?
 
#24 · (Edited)
Yes it is grounded correctly. The digital distro block is grounded to the frame and I have my two battery grounds (one to the trans and the other to the taillight ground, see pictures below). I have actually narrowed the problem down to my HIDs. When the headlights are off the digital distro block reads the correct voltage. However, when I turn the headlights on that is when the display will read 0.00 V. I originally had the HID harness +12 V attached to the under hood fuse box. I contacted Cullen at RSX Retrofits where I purchased my HIDs and he suggested running the + 12V from the digital distro block. As you can see from the pictures I have tried this as well and have ended up with the same results. To be honest I am out of ideas except to try another digital distribution block...

Side Note: My digital distribution block is wired as follows.

Input: 2 AWG Power Wire
Output 1: Starter (250 amp ANL)
Output 2: HIDs (60 amp ANL) Has a 25 amp in-line fuse
Output 3: Under Hood Fuse Box (100 Amp ANL)

Headlights Off:


Headlights On:


Trans Ground


Circuit Breaker (100 Amp)


Battery
 
#25 ·
You can make a cheap Faraday cage to go around your HID ballast, ground it, and see if the problem goes away. If you do it correctly and it doesn't solve the problem; I assume that the interference is traveling along the power wire (harmonic noise). In that case; you could try a cheap car stereo power line filter (protects stereos from alternator/coil interference). But it would need to be able to safely pass the amount of juice that your HID kit draws.
 
#26 ·
Thanks for the suggestion. I am very much a beginner when it comes to audio interfearence issues. The power line filter that you mentioned would that be something like a ferrite core noise suppressor?

 
#27 ·
Ferrite is a stone or mineral, I think. A Faraday cage is a metal enclosure that's grounded and keeps electro-magnetic signals from passing through it. Google it and you'll that it can be complicated or simple.

You could probably experiment with a small cardboard box lined with aluminum foil. The foil has to be touching metal directly or via grounding wire.
 
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