1st gen 105 amp bolt in alternator.

True. Lmk when you order. Split shipping

 

For sure, people go hog wild for no real reason sometimes. I guess they like the challenge, lol.

Yeah, but you have a 105 amp alt, so that'd be 6 gauge...

But that's a MINIMUM.

If you're going to do the wires, just go 4 or 2 gauge at least. Most guys seem to run 1/0 or welding wire for the Big 3. You can just run a larger loom and everything will look totally stock(ish).

4 gauge:

$33 Sky High Oversized 4 Gauge AWG Big 3 Upgrade RED/Black Electrical Wiring Kit

https://www.amazon.com/Sky-High-Ove...41428&s=gateway&sprefix=big+3,aps,253&sr=8-15

1/0 gauge:

$44 Sky High Oversized 1/0 Gauge AWG Big 3 Upgrade RED/Black Electrical Wiring Kit

https://www.amazon.com/Sky-High-Ove...41241&s=gateway&sprefix=big+3,aps,253&sr=8-10

Going this "oversized" and you don't need to worry much about going with the nicer OFHC wire, but even 1/0 gauge ofhc wire is only $60. Cheap insurance when you consider how much a car fire costs...

$80 GP Car Audio Big 3 UPGRADE wiring Kit OFC TRUE 1/0 AWG GAUGE RED and BLACK

https://www.amazon.com/GP-Audio-UPG...341820&s=gateway&sprefix=big+3,aps,253&sr=8-6

 

I would be interested to see how many amps this puts out on a bench test. Just to see if it's truly 105 amps. Then I can decide what wires to get, especially since all of these charts are terrible and list 105 for two gauge sizes. I also don't want my engine bay to look like spaghetti.

 

Personally I’d probably run 4 gauge. At idle I’d assum this thing can put out at least 90 amps. Densos typically are close to rated performance at idle

 

sure, you could go do a bunch of tests and see exactly how many amps it puts out in various conditions, then get the minimum wire gauge for that application, or just spend $45 and get the 1/0 gauge wire kit that would be more than enough for any alternator you put in.

The different gauge sizes are for if you have extra long runs of wire. The longer the wire, the more the current will "bottleneck" inside the wire, so you need a bigger gauge wire for longer lengths. Wires for the big 3 are usually 3 feet or shorter, so you don't need the bigger gauge as it is rated.

IMO, the only reason to use the minimum rated wire gauge is if you're concerned about cost. Saving a few cents per unit will save tens of thousands if you're Toyota pumping out hundreds of thousands of units. For those of us with one unit, even if you get the nicest biggest wire you can get a hold of, that's really only a $40 or so difference in cost.

You can make the wiring look as good or as bad as you want. A 2 or 3mm difference in the diameter of the wire isn't going to crowd the engine bay. You're replacing wire, not adding wire.

 

I know all that. Just curious what the output really is. Maybe someone on here has the means to check.
Are there any write ups on how to redo the wiring *cleanly*?

 

Looks ,like these are shipped out of California from rockauto for me anyways.

It will arrive just in time for the week project

 

Sorry, didn't mean to sound like I was talking down to you or anything.


As for write ups, not really sure. Most of the ones I've seen don't go into a lot of detail about where exactly the places the wires to make it look nice, they usually just follow the stock wiring. You kinda just have to get in there and play around with placements until you get what looks good to you and doesn't interfere with hot or spiny things, then trim and make your connections. More than likely that'll just be the same route the stock wires take just with a larger loom to cover up the larger wires.

Found this stuff that comes in different colors which might be kinda cool looking.

$17 Electriduct 1/2" Split Wire Loom Tubing Polyethylene Corrugated Flexible Conduit (0.5" ID) - Black - 25 Feet

https://www.amazon.com/Electriduct-...ds=wire+loom&qid=1569359692&s=gateway&sr=8-16

Found this actually...
https://www.tacomaworld.com/threads/big-3-upgrade.561064/

on page 3 there's this beauty:

 

Well it has 105 written on the alternator and denso is a very reputable company so I feel pretty confident in that.

The way it works is they take amperage measurements at different rpms, the more rpms the more amps, then they divide and find the average which gives the advertised output. Now also consider that output is based on demand so what tests on the bench will be different for the vehicle. Now add in the variable options we have such as stereos, lights, winch and so on which all play a part in draw. So readings at each vehicle will very, just because guy A measures X and guy B measures Y with the same alternator does not mean that one setup it working better than the other, it just means one has a bigger load at a given RPM. That is why we generally go by volts in stead of amps, it's easier to see. If the volts stay high your system is sustaining its self, if not the volts drop and a higher amp alternator may be needed. Having alternators measured in amps and tested in is confusing, so hopefully helps explain why that is.

 

Great info. I may have to jump on this as well.

 

Who is going to disassemble and compare the stock alternator and this 105 amp amplifier? Post some pictures! Is it the regulator that's different? The rectifier? etc?

 

One way to get an idea of needs/performance would be to install an ammeter.

A guy could just install the shunt and skip the meter itself, instead using a multimeter to read the shunt voltage.

https://www.bluesea.com/support/articles/Metering/552/Sizing_a_Shunt_to_a_DC_Ammeter

 

Hey @chagovatoloco I have a question: do you think you could look in your parts catalog there at work and see what year(s) and engine types on the Vitara take this alternator?

Some of us who love to have a reason to hit the salvage yard might find a used one.

 

Just make sure it says 105 on it or cross the number on the alternator, some of the Grand Vitaras are 80 amp and other 105 amp.
The OE number you want is 31400 - 52D00.

 

So I looked to see what options there are for the increased amperage and what might be needed if anything.

Essentially from what I found it says that all you need to do is upgrade to a thicker wire gauge 4 or 6
and run it directly to the battery from the alternator and the same with the neg side as a ground strap.

Is this all correct? If so this is pretty simple.

 

Where the second big red wire going? In the last pic

 

Starter.

 

The factory wire is pretty small, so going to a little bit bigger wire may not be a bad idea. I found some 6 gauge in my garage so I'm going to go with that, but don't over think it.

 

Fuse box?

fuse box?