32 GTR battery relocation circuit breakers

[AlexRichardson]

Looking at relocating my battery in my 32 to the boot, where in the circuit and what breakers should i put in it? any info much appreciated.

[shaund]

There is a thread on gtr.co.uk with some detail.. I'm about to do the same on mine.. I got 300A stinger breakers.

I'm running 35mm^2 cable from the battery in the boot up to the front and will be attaching it where the battery was originally connected.

Do volt drop calcs for the length and size of cable you plan to run, remembering peak current draw on starter motor could be 200-300A, when its first breaking free. this should drop rapidly to somewhere in the region of about 150A.

Use a drycell fully sealed battery. I got a fullriver HC35 for $200 from a local battery supplier - this will fit on its side under the rear strut tower brace.

 

Good luck!

[powerdbygarrett]

On 7/13/2016 at 1:49 AM, shaund said:

Use a drycell fully sealed battery. I got a fullriver HC35 for $200 from a local battery supplier - this will fit on its side under the rear strut tower brace.

Can you point me to any pictures of this please. Thanks

[shaund]

7 hours ago, powerdbygarrett said:

Can you point me to any pictures of this please. Thanks

I ended up putting in 2x HC35s in parallel, and used an ANL fuse holder with 250A fuse because my 300A stinger breakers were lost in the mail.

I fabricated an aluminium panel for a giant on/off switch, the ANL holder and a small fused distribution block for things like fuel pump and stereo.

To hide it all away I fabricated a wooden panel covered in matching fabric and some metal brackets to cover it over to hide it away.

I'm pretty pleased with the result.

Battery spec sheet: http://www.fullriver.com/products/admin/upfile/HC35.pdf

Fuse Holder: https://www.jaycar.com.au/anl-in-line-fuse-holder/p/SZ2078

 

[jmknights93]

4 hours ago, shaund said:

Woah, that looks like such a clean setup. Do you have any other close up photos?

[powerdbygarrett]

14 hours ago, shaund said:

I ended up putting in 2x HC35s in parallel, and used an ANL fuse holder with 250A fuse because my 300A stinger breakers were lost in the mail.

I fabricated an aluminium panel for a giant on/off switch, the ANL holder and a small fused distribution block for things like fuel pump and stereo.

To hide it all away I fabricated a wooden panel covered in matching fabric and some metal brackets to cover it over to hide it away.

I'm pretty pleased with the result.

Battery spec sheet: http://www.fullriver.com/products/admin/upfile/HC35.pdf

Fuse Holder: https://www.jaycar.com.au/anl-in-line-fuse-holder/p/SZ2078

 

Thank you! That is pretty much exactly what I was looking for. I was also planning to make an MDF board to cover everything. I have done the same in my past cars. Question, How did you secure the batteries to the trunk? Did, you drill holes through and bolt them underneath? That's something I am trying to sway from. In the states these cars still cost a ton of money. Don't really want to be drilling extra holes yet.

I was thinking of having something like this welded onto my rear strut bar to secure the battery. I couple guys I know run this in their E30.

What do you think?

[shaund]

I made up an aluminium plate with rubber glued on the top for the batteries to sit on. Under this, I have 2x steel straps with holes that bolt through the floor, and then allow some threaded rod to extend upwards to another steel strap on top of each battery.

For the bolting to the floor, I used painted steel plates underneath the car to re-inforce, and stainless fastners, loaded up with black sickaflex sealant. The bolts go through the aluminium plate, through the metal straps, through the floor, through the re-inforcement plate underneath and then nuts with lock washers bolt it rigidly to the body. Getting the re-inrforcement plate under the floor and getting it all bolted up was really difficult... It'd be easy if the rear subframe and/or diff was out... but its doable without removing anything from underneath if you have a second person on top to do up the bolts for you.

The idea of welding a bracket to the strut tower brace is neat.. should be solid enough too. I think thats good for an "easy bolt-on", but I don't see it as a big deal to bolt through the floor if you goto the effort to make sure its sealed and rust proofed.

 

You also probably don't need to use two batteries of the size I used. I've seen some dedicated track cars that use a single battery half the size of one of mine.

[Carbonsky]

Man this is a really clean install. I just completed mine but I'm having some serious issues with the power after it leaves the distribution block. Smoked my radio literally and blows the power distribution fuse I have dedicated for interior. 

[shaund]

the only thing that'll cause a fuse to blow is a short circuit or faulty equipment...

I'm not sure how you'd manage to 'smoke' your radio... did you some how reverse the polarity to it?

The way I wired mine was (and this is not a guide or how-to, no warranty, seek professional help, blah blah)

After mounting the new batteries and removing the old one:

1. Cut down the battery ground strap to remove the excess length and thereby the negative terminal that normally bolts to the battery (car body is your ground).

2. Make an electrically sound new ground for the battery in the boot.

3. Install a postive cable from new battery in boot (with appropriate fuse/isolator in the boot) to the front of the car

4. Join via a busbar onto the original battery positive terminal. This is installed inside a well insulated box that is hard mounted in the engine bay.

I maintained the original fuse box, fusible links etc in the engine bay - I saw no need to change this - it didn't need improving.

 

Its critical to remember that there is enough stored energy in your car battery to create a fire very quickly. If you're improperly fused and you get a short circuit, there is a potential to set your car on fire. Electricity often doesn't get the respect it deserves. With a single average car battery you often have a fault current (short circuit) in the region of 1000A.

looking at how your power distribution block is mounted to the body in the engine bay, it looks like its just got a thin sheet of plastic as insulation between it and the body (ground). I'd be re-thinking it a bit to see if some more insulation can be added - a piece of thick strong plastic as part of the mount, and/or or a decent thick plastic box to enclose it.

Do you have a fuse at the battery end? What size is it?

 

My intention is not to be insulting or unhelpful, but If you're not 100% certain of what you're doing, at the very least seek the advice of a competent auto/commercial electrician, or electrical engineer. It'll be cheaper than replacing a car that gets burnt to the ground by an electrical fault.

 

Cheers!

[Carbonsky]

Thanks for the reply! Any advice is well received. So I have a 250A fuse in the rear right off the battery. This has remained intact and hasn't blown at all. I also right off the battery in the rear have kill switch/circuit breaker on the negative side (to prevent breaking continuously breaking the positive) when disconnecting the battery. This circuit seems fine all way up to this distribution block in the picture where every time the car is started the positive lead that powers the car blows the fuse (60A). My other two circuits starter/alternator and other components remain intact. So I was thinking if it was a short to ground due to that block every fuse in that block would pop as the other two fuses are 80A (starter/alternator and another 60A for the components. So key on engine off all interior and voltage holds at 12.5v clean and no issues. New information! I recorded a video under the bonnet as I started the car and found the voltage display on that distribution block was climbing to 18volts! (see pic). Other weird thing is that the other fuses go dark and the one interior fuse/power stays lit blue until it pops. All things considered  first thing I begin to think of is voltage regulator on the alternator or bad battery, but do you think that is could be purely coincidence that one of these has failed in that small window of moving the battery or could I be still dealing with some bad ground or short? Thanks again for your insight.

[Steve85]

@carbonsky Based on your description above all of the power in your circuit is going through that one fuse. Is it possible that the circuits are bridged elsewhere in the car?

Also if you have a normal car battery you shouldnt be seeing a voltage increase while cranking. If anything it may drop to the maximum power of the battery (less volts but more amps). Is it possible you have the batteries in series not parallel?

If it were me, i would draw my circuit, then confirm each point on the circuit you imagine, vs what you have in the car. For me drawing my circuit always brings clarity.

Not judging, just trying to assist!

[Carbonsky]

@Steve85 any advice is appreciated! I only have one battery, I believe @shaundhas two. I have the normal voltage drop during cranking, it's about 5secs or so after that, that the spike happens (18v) and that circuit (interior) fuse blows. What I will do when I get out of work is remove that wire/circuit from the box pictured above and start the car again and see if the voltage spikes. If it does then something crazy has happened and shorted somewhere (I say crazy due to the fact I haven't touched anything else). If the spike continues I presume I could "coincidentally" have a bad voltage regulator/alternator go out. Or that distribution block is junk, but I did move the circuit over one and the fault (blown fuse) scenario happened wherever I moved it and the other circuits stayed intact. The only thing I did differently than others was remove this (see pic) when I cut the positive leads off the OEM terminals. Don't think this would cause any unstable voltage nonsense though.

@Steve85 I don't think all my voltage may be going through that one circuit as I can still start the car after that fuse is blown. I just didn't have the thought to observe if the voltage spike was still occurring after fuse was blown. Basically the equivalent of removing the circuit from the equation. 

[Steve85]

Silly question for you... what is that? ^^^

Is it just a connector?

[Carbonsky]

On the R32 positive terminal OEM looks like this (see pic). Basically there was the 2 gauge (bottom cut in pic) that powered the alternator/starter, then the 8 gauge (next cut wire up) which seemed to power all of the systems under the bonnet (pumps etc) and the top connector 16ish gauge (gray wire) powered the interior. Notice that little gray wire ran into a connector that stepped up to the 8 gauge white wire. So I was replacing my headlamps and as I was removing the battery terminal this little grey wire was barely hanging to life. It was so brittle and barely together. Amazing that with all the driving that I had done this thing was still together. Since it was so brittle I cut it out and kept the 8 gauge as it fit the distribution block pictured in the thread above. So the alt/starter stayed the same size, the second positive lead also stayed the same size 8 gauge, but I cut that 16ish  gauge wire and just ran the 8 gauge that you see on the other side of that respective connector. At one point I thought there may have been some resistor in here or something but then after I discovered the voltage spikes I figured it to be irrelevant. @Steve85

[shaund]

I tend to not trust the volt meters in distribution blocks like that... I'd double check with a decent multimeter (something good like a fluke or a higher-end affordable brand is fine too)...

As suggested by @Steve85, a drawing would be good.. so far your description sounds like you've done the right things though...

If we make the assumption that the 18v you're seeing on the distribution block's meter isn't false, Its possible in your re-wiring that you've somehow dropped the voltage sense line from the alternator, and the alternator is just outputting maximum voltage based on RPM.

 

Most alternators will have 3 basic connections.

Ground, Charge, and Voltage Sense.

Ground goes to the body, Charge is a big fat wire that goes to the battery to charge it, and the Voltage Sense line is a skinny wire that should go directly to the battery to sense voltage at the battery. This allows the alternator to adjust is voltage regulation up when the electrical system in the car is under heavy load, or if the battery is flat, to make sure voltage is regulated at the battery.

Have a look in the workshop manual and see if you can find the part of the wiring diagram that deals with the voltage sense line, and identify it on the plug on the alternator. measure voltage with a multimeter between that pin on the harness and the negative terminal on the battery - you should see +12V.

 

As an extra diagnostic, assuming your battery is good, you could disconnect your alternator completely from the car electrical system (be careful to insulate the big charge lead at the alternator side) and run the car without the alternator. If it starts, runs, behaves normally, and you don't see the voltage spike, it may be alternator or alternator wiring related.

[Carbonsky]

@shaund

@Steve85

Due to work, holiday, and projects for the Mrs. I finally got around to disconnecting and removing the alternator. After disconnecting the two 8 gauge power wires behind a 10mm nut and wrapping with sufficient electrical tape I started the car and voltage held at 12.3v (eventually dropped to approx 11.9v, no charging system of course). But no smoke or 18v spike. I continued and removed the alternator and will take it and the battery to an auto shop in hopes to have them benched tested. 

[Steve85]

Interesting... I wonder if the alternator was receiving a bad or unknown voltage. If it thought that the battery was low it would kick it hard to try and charge it up.

Let me know what the auto shop comes back to you with. Even if they say they are both fine, it will be good to know because we can narrow the issue further.

Good luck. Steve.

[Carbonsky]

Will do. Thanks! @Steve85

Unfortunately I'm about to start another thread due to an issue I discovered while removing the alternator. Check it out please as you may have some good insight and it's always appreciated.

[shaund]

so it sounds like your alternator was producing the high voltage.. could be sense line not connected,short circuited, or some other issue; or faulty regulator perhaps.

 

I'll check out your other thread too.

[Carbonsky]

Hey @shaund so as in this diagram the alternator has essentially five wires going on to it. It's appears to tap power from the 75amp fuse coming off the batt. Breaking it down "DA05 & DA20" labeled "A" at the alternator (will have to zoom in) the two wires going in together are the main power leads. The section labeled "L" is the appears to be the main ground. Which leaves "DA09" labeled "S" and the other ground "M" as a connector that plugs into the side of the alternator. I guess my question is, is this the voltage sense you're speaking of or is that the connector for the internal voltage regulator? Or are we saying the same thing just different lingo?