Hi all. I've been doing some reading on battery relocation and had a few to ask before I start the work. See sig for general mods. I have no crazy amps or anything like that. Just a basic turbo car and have to relocate the battery as my charge pipe is coming up that area. I plan on usin the grommets behind the PCM and run it along the passenger door to the rear spare tire area.

1. If I'm planning on doing a killswitch later should I run 2 positive cables? The other being for the alternator later on?

2. Will 2gauge be sufficient? It's what I got in my battery relocation kit(Taylor 48101)

3. If I ground the negative terminal in the rear what should I do with the negative up front? Any pics of how you grounded that terminal?

4. Is there any enclosed battery boxes that fit like a glove in the spare tire area? I saw tue bmr option, but it's not enclosed. Looked slick though. If not I guess I can hack the Taylor box up a bit to make it fit.

Sorry, Electrical isn't my strong suit.

 

I just did my battery relocate and when done right took me a good amount of time. This is how I did it and I did not listen to the tech sheep and although the car has not been started due to front end apart right now I have tried to spin it over and it was perfect.

The battery I used was a Braille 3121 that weighs 21lbs. Cost me $178 through summit with a 2 year warranty. I did not want to run a large Red top as the whole purpose of a battery relocate is to take weight off the front and move to the rear. However I feel if you are doing something try every way possible to lighten it up as much as possible. The extra wiring ect is heavy so I tried to offset that with a race battery.

With the battery in the back with a Burkhart kit I ran my 2 guage wire from the positive terminal to the off side of the switch (I mounted my switch in the center of license plate) Then 2 guage wire from the on side of switch thru right side of car interior thru a grommet on right side of lower dash by PCM harness, behind the PCM and down to the starter. I ran a 2 guage jumper wire from the starter to the fuse block running along were the elec fan wires run all in loom nice and clean. I then ran a 4 guage wire from the altenator following the main power wire back to the positive side of the battery, NOT the switch. In the back as close to the battery I ran a 4 guage 150 amp in line fuse. I grounded the battery to the rear seat belt stud. I removed all factory wiring for the battery and removed the factory ground wire from shock tower to the engine and ran a new ground with leftover 2 gauge wire. The only issue I have yet to make sure works is the charging due to not being able to start the car obviously. Again this is the way I have done it. I see too many hacked up pics of battery relocates on this site I am suprised cars are not burning to the ground. This job took me all of a sunday pulling things apart ect and 4 evenings about 2-3 hrs each and a few hrs the following sat to finish it up. I will try to posts pics of my install. Hope this helps.

 

Where are you guys putting your batteries, on the bracket that I have seen for these cars that puts the batteries in the passenger side rear wheelwell, or in a box?

 

I just finished my battery relocation in my car. 2 gauge should work. I used double ot for a short ground in the back. The front ground needs to be bolted tightly to clean metal on the body somewhere. Weld on a stainless stud or drill a hole for a bolt.

Hey 03Busa where did you find the 150 amp fuse?

 

That was the hardest part of the whole project LOL, the only place that I could find was a local radio/stereo installation place. Best Buy, radio shack ect. No body carries the stuff anymore. I wanted a 200amp but that doesn't exist on the planet. Working on pics as we speak.

 

pics:

 

More pics

 

pics...

 

Thats def a clean install BUSA, nice work and thanks for the pics

 

Don't you need a box or a bulkhead to be NHRA legal?

 

Not sure with a dry mat battery. Either way most tech tracks around here will never even notice once the rear panel is put back on LOL.

 

yes you need a box or bulkhead nomatter what battery is back there. Also a cutoff switch that works to be technically legal at NHRA tracks

 

^^Not sure if you were refering to my cut off swich or not but my setup is functional and works. Just decided against a push/pull setup.

 

nope just stating the rule, so nobody gets misinformed about the bulkhead or sealed box question. Push pull or a turn switch are perfectly legal. But they do actually need to shut the car off while running as well, so I added that part so everybody got it

 

Correct, that is why there is a separate wire dedicated to the altenator. The same reason you can swap a car battery with a stock setup with it running the 3 power wires are "spliced" together and will allow the car to run off altenator while swapping batteries.

 

I could be wrong. I thought they chaned the rule to require the battery to be a push off. I thought you cannont even have a pull off anymore, to make it a simple common way to shut off the car in an emergency, and everyone at the track knows every car is a push off.


Could be wrong, i didn't memorize the rule book, maybe someone else can chime in.

With the dry battery you can do a rear firewall then you dont have to have the battery in the box, but if you ever put a cell in the t top hole, then you will need a battery box to seperate the battery from the cell again.

Being a dry battery saves you from having to have a vent.


Thanks, Chris

 

So an optima red top doesn't need a vent in the box?

 

I believe you are right. You also have to have it labeled Push Off or if its a rotary, the direction that is off.

 

Under normal conditions your battery will never give off any gas. If it is overcharged it would open its safety valves and release gasses.

Technically i dont think you need a vent.


Chris

 

paraphrasing (ALOT) General Regulation 8 (section 20 of the 2011 rule book)

Rear firewall of 0.024 steel or 0.032 aluminum required if battery relocated to trunk. IF firewall not used, same thickness box or poly (approved NHRA box) must be used. Box must be vented to outside [[[ doesn't differentiate between Optima style or regular lead-acid batteries]]] 3/8" minimum bolts must hold down the battery with a metal hold-down strap (no fabric or plastic straps allowed)

As far as the cutout switch - - - General Regulation 8:4
If the battery is relocated, a cutout switch is mandatory. Cutout must be connected to the positive side of the electrical system... if it's a push/pull type, push MUST be the position to kill the electrical. plastic or keyed switches are prohibited. (doesn't say permanent rotary isn't allowed) just that the OFF position must be labeled clearly.


There's more, but thats the general gist of it.

GL!