BIG 3 wire upgrade?
 

So I am trying to find more info on the big 3 wire upgrade. I tried doing a search but was unable to locate anything relavant. If any one has a link to this info would be great.

It involves using a 3" solid core copper positive battery cable. They're very hard to find these days and cost about $800/foot to purchase.

Good luck.

:lol:

Just kidding...

Big 3 refers to upgrading the wire gauge sizes of the main 3 wires in the electrical system.

1) Battery negative to chassis
2) Alternator to battery positive
3) Chassis to engine

Btw, I'm really surprised that the search you did came up with nothing on this...

Maybe try google after you search yotatech.

A quick google search turned this thread up:

link

Thanks for the link, but i was looking for some thing more 2nd gen 4runner.

Same concept. Heavey gauge wiring between battery negative and chassis, alternator and battery positive terminal, and ground between engine & chassis.

Ok lets look at these for the early 90s trucks. With all of these you can either replace the existing wire with bigger wire or (my favorite) leave the existing wire in place and run another wire parallel to it.

#1 is easy, just a little short wire in plain view that screws to the body on the inner fender. Take the time to clean the body sheet metal with some sand paper.

#2 is the hardest on our trucks because the battery & fuse box is on the other side of the engine bay from the alternator and the wire goes from the alt to the fuse box then to the battery. I took the fuse box apart so I could connect the parallel wire directly to the same connection points as the stock wire. Make sure you route this (+) wire where it won't get cut or damaged and protect it well with split loom. Remember (+) wires that get cut and grounded on something can start big fires!

To the alt:
http://thumb7.webshots.net/t/46/46/6...7Jttqbu_th.jpg

I almost forgot if you upgrade the battery to the fuse box wire you must keep the fuseable link that is right off the battery (it is the smaller section of wire about 4-6 inches long). If you add a second wire parallel it also must have a fuseable link (This was one place I upgraded the existing wire rather than adding a parallel wire. (not sure how safe it is to add another fuseable link).

This is what my fuse box looks like after the upgrade, I used 4 gauge from the fusebox to fuseable link and the fuseable link is connected directly to the battery:
http://thumb7.webshots.net/t/34/34/0...7uTBXUD_th.jpg

#3 Bolts to the block (probably very dirty so clean up the contact surface) and runs to the battery (-).

Would there be anything wrong with running a wire (2ga) from the alt to the battery with a say 125amp fuseable like (100 amp alternator), and just leaving the stock setup? I am not worried about anything drawing more than the OEM wiring can handle, except what is atteched to the battery directly.

AH62ID - nope, no issues atall. My 1/0 run from the alt to battery is unfused actually...

What helps everything a lot is grounding redundancy. I have 2 grounds to the chassis, one at the OEM location and one behind the charcoal canister on the fire wall. I have 2 grounds to the engine, one to the block and one to the head. The last set of groud that I havent done are going to be from the frame rails to the block and to the battery.

And while im in there im replacing the OEM wire that feeds the fuse box with a nice fat 1/0 if itll fit...

My dad is a boat mechanic so I know well all about proper grounding, and how DC is differnt than AC in that it needs to return to the start point, hence a good ground.

With the engine out I plan to beef up the chasis ground, and then block ground. I alreay have a huge frame ground. When I wired my winch I ran cut the ground in half and bolted it together with one of the bolts holding my ARB on, so I think its grounded well enough..

As far as the alt wire, I figured that was safe.. but none the less I will probally acquire a 125 fusable link just to be safe. It should really help when winching.

I had my OEM alternator rebuilt with a toyota 100 amp winding, then put a smaller pulley on it so it puts out max amps at about 1500rpm. The only issue I have is it still goes offline at about 700rpm. I havent figured it out yet since the guy who built it said it should be putting out about 35-40 amps at that speed, must be part of the OEM voltage regulator.. .I wonder if there is any way to fix that....

See post #19 here: http://www.tacomaterritory.com/forum...ght=Alternator

The fuse sounds like a good idea to me, if you do connect the alt straight to the battery. In a perfect world you wouldn't need any fuses, but ˟˟˟˟˟ happens.

Cool thanks, I'll get a hold of them, and the guy that did mine to see what was and wasnt done.

The guy who did it does all the the rebuilds on alternators and starters for my dads boat business. He does good work, just doesnt work on too many toyotas :D

I found the 4 gauge to be a pretty tight fit in the fuse box openning. Bigger and you may have some extra work. IIRC the stock was about 8 gauge so going to 4 gauge is a pretty big upgrade (looks to be about double the OEM wire to me)

this is true and you are correct I should have fused my alt to battery line.

Cool this helps alot thanks guys.

I was looking at that tread again.. My alt put out aperage at low rpm's on the bench, just not in the truck. Is there something in the truck that would prohibit that?

wow the peeps on that site LOVE the 3.0 I see. Too bad they dont realize the 5vzfe has just as big a HG recall as the 3vze...lol

The alternator generates current as the electrical system needs it. Voltage is the best indicator of whats going on in your electrical system. You probably never saw that much current in the truck at idle but your voltage was probably at least 13.0v or so....which means it's workin fine! :D

I know its offline, or so it seems, as my lights dim and my ARB compresser slows down.. but as soon as I hit 755 rpms its putting out serious energy, but at 750 or lower... nada

ah thats normal, my 190 amp unit used to not turn on until about 1100rpm...

In your case though you can just bump the idle up to 800 and not worry about it! :D

What I thought was odd was I put a much smaller pulley on it and nothing changed.... so what causes that? Why will it put power at idle rpm on the bench, but not in the rig?

So the positive battery cable has that break off wire that goes to the slow-blow fuse. That wire from the fuse goes to the alternator??? There was another post from long ago that I found in a search that talked about that wire going bad and maybe being a little small and showing how to upgrade it. I think I posted a link to the starter of this thread on his other thread, but if what I am putting together from that other post and this post. That is the wire that the alternator connects to the positive battery cable. My battery light comes on where there is no charge going to the battery and then a little while later it will go off. This could be the issue for me. I will have to upgrade all four of the wires to be sure. If I am right, we should change it to the big 4 wires.

1. + Battery to Slow-Blow fuse
2. Slow-Blow fuse to Alt.
3. - Battery to chassis
4. Engine to chassis

Thanks for the insight.

:banger:siris

If you dont mind me asking, with what parts did you rebuild the alt?

I dont have a clue, the guy who rebilt it said he found toyota parts to beef it up.

A few notes:
1) You shouldn't parallel fuses/fusable links of X amps. Current travels through both paths and assuming you just added another fuse of X amps, the net result is putting 40 amp fuse in a 20 amp circuit. It'll take twice as many amps to trip that fuse and that can be a bad thing... I'm not saying that you should NOT put a fuse/fuse link - I'm saying if you're using both circuits, you should divide the fusable link by 2 and use 2 of them in parallel.

I always upgrade my electrical system on early toyotas. The factory wiring gauge is simply too weak for 15-25 year old vehicles. I use 4ga wiring to the starter and to both ground points. I see no reason to use better wire than 4ga for our electrical systems.

If you've got a big alternator, replacing that wire should be manditory.. On 1st gen pickups, I've seen the stock alternator wire get old, start to heat up, and generally go bad on that weak-ass 40A alternator. If the wiring is in good shape (it tends to go bad at either end) and you've got a stock alternator, I wouldn't mess with it...

Just my .01.

I went with 1/0 everywhere since I compete and every 0.1dB counts, and well, big wire is cool as hell too! :D

Clarification please: Tad bit old I realize, however if I was going to be doing the 'Big 4' as it were, assuming I run:

1. + Battery to Fusible link (?)
2. Fusible link to Alt (4 gauge)
3. - Battery to chassis (4 gauge)
4. Engine to chassis (4 gauge)

Anyone know what size fusible link I should replace the stock one with? The stock seems to be an 8 gauge fusible link if I had to guess.

What you might consider instead of a fuseable link is getting one of those big fuses they sell for high end stereo amp wiring (like say 100 amps). I've got one for my main power wire going into the cab that I found at Ultimate Electronics.
It's on the big red cable here right off the battery:
http://thumb7.webshots.net/t/53/453/...7PcFWXC_th.jpg

I would always carry a spare, or leave the OEM wiring intact as well....

Yeah good point.

So is it even worth it then to upgrade the fusable link between the battery and the stock fuse box? Am I correct in assuming this would make for better current flow between my optima and the fuse box and alternator and optima? :hillbill:

I intend on leaving the factory wiring intact, but adding a 2 or 4 gage battery-alternator with an in line 100 or 125amp fuse

and then run various grounds from various locations, battery to chassis, intake manifold-chassis, block-chassis.

IIRC I kept the factory fuseable link in place, I don't think the fuseable link section is long enough to have any measurable voltage drop.

The only reason I was going to do this upgrade was I had my OEM alternator rewound to 100amps... and for winching I was going to put a hand throttle in.. well the hand throttle nor big 3 got done, but I will probally beef up the grounds on my 07. The Tow Package has a 130 amp alt, so the wiring shoud be good... but in order to use a chassis ground I want to beef the grounds up...

Back on topic.. I was going to leave the OEM wiring 100% intact and just put a seperate wire from the alt in to the battery, this way I dont have to remove stuff, and if either fuse were to go (doubtful), i had a backup. This would also allow me to run the second wire to the top post, which is the one Optima wants for a winch, so the power would have been more direct.

Electrical Rookie
 

This thread is very helpful, but being an electrical rookie, I am getting frustrated.


My Runner has a bad ground somewhere and is giving me the ever popular single click. I can get it started with jumper cables acting as a faux ground.

Two questions for all you sparkies out there:
1. Where is the chassis to engine ground?
2. Is the negative terminal cable supposed to run to the passenger side motor mount or the block?

I don't know if someone already suggested this, but you might try 1/0 ga welding cable. It's much more flexible, durable and "dense" than battery cable. I used it on an old car that I wired from scratch and it worked great!

IIRC on my stock 93 ext-cab 3VZ-E:

1. There was a ground from the middle-top of the fire wall to the intake manifold.

You can see the ground here bolting to the intake just behind the V6 3.0 EFI name plate
http://thumb7.webshots.net/t/57/457/...7JqYLZp_th.jpg

2. After reviewing some pics it looks like the passenger side motor mount, but the block would work just as good. The wire is off in this pic though.
http://thumb7.webshots.net/t/20/21/0...7oecvUQ_th.jpg

Yeah I used welding cable a lot, but usually not that big. I think the biggest I used was 2 gauge, usually more like 4.

will these upgrades work on my 82 4x4 truck. If not ideas please cause my alternator keeps dieing and comming back on causing my battery to die.

They will work on any rig, thou I doubt thats your problem.

In desperation I replaced that one wire on my truck with an old piece of 8 gauge power cable and some cheap crimp on ring terminals on a whim to see if it would help and it fixed 99% of all of my electrical issues...

Funny thing is that several years back I had a charging issue and the electric shop I had work on it replaced that wire and soldered all of the connections on the replacement. The only thing they did that I questioned was they used a long piece of fuseable link right off the battery that I always wondered how well it would transfer current.

Now that I know that was most of the problem it's time to save up and get larger gauge cable to redo that and the rest of the '3' and add fuses.