Knowledge dump: Big 7 battery cable upgrade; high amperage alternator; wiring

TL;DR You need part numbers 90980-10868, 90980-11349, 90980-11400 in order to rebuild the alternator-starter harness on your first generation Tacoma with a 2RZ or 3RZ engine.

I invested in the Jeep Cables Big 7 kit and 140 amp alternator from LC Engineering for my 1997 Toyota Tacoma 2.7L 4X4 W59 MT.

There is plenty of information already on TacomaWorld concerning bespoke battery cables and aftermarket kits, like the Jeep Cables Big 7, so I won't go into detail concerning lugs, crimping, etc. Instead, I want to share information concerning:

1. How I sheathed, configured, and installed the Jeep Cables Big 7 Kit
2. How I approached the alternator-starter wiring harness

Really, the second point above - more precisely, the seeming absence of any information concerning the alternator-starter harness fed by the fuse box on TacomaWorld - is the raison d'être of this post.

Big 7 battery cable kit

• I sheathed the cables using 1/2" and 1" 2:1 polyolefin heat shrink in black from Waytek.
• I sealed the cables using 1" 3:1 polyolefin dual wall heat shrink in black from Waytek.
• I labelled each cable using the
  $124 DYMO Industrial Label Maker | Rhino 5200 Label Maker, Time-Saving Hot Keys, Prints Fast, Durable Label Maker for Job Sites and Heavy-Duty Labeling Jobs
  Dymo RhinoPRO 5200 and 3/4" heat shrink labels from Dymo.
• I sealed the labels with
  $8 XHF 1/2" (13mm) 3:1 Waterproof Clear Heat Shrink Tubing Marine Grade Wire Cable Adhesive Lined Tube Insulation Seal Against Moisture Corrosion and Air Leakage, 4 Ft
  1" 3:1 Ethylene Vinyl Acetate heat shrink from Amazon.
• I housed the 150 amp alternator fuse (which comes in the Jeep Cables kit) in a
  $26 Blue Sea Systems 5005 ANL Fuse Block with Insulating Cover, 35-300 Amp, 32V DC
  Blue Sea Systems ANL fuse holder which I bought from Amazon. I attached that fuse holder to the factory fuse box using hardware from Home Depot. Choose a small, discrete set of hardware to avoid contact with relay hoods.
• Installation tips:
  • You will need to map the wires according to your engine bay layout. I cannot provide explicit instructions here. My advice is simply to go slow, and go one wire at a time.
  • The mounting point for the engine ground is prone to stripping. Do not torque this bolt too hard, therefore.
• Miscellaneous tips:
  • Attach the PDC (factory fuse box) wire (it is the smallest gauge wire) to the post at the top of your factory fuse box. If you are skeptical of that method then open your factory fuse box and look at how the fuse box distributes power from the 80 amp alternator fuse to the rest of the fuse box. You will understand why simply using the post atop the factory fuse box - the little threaded bolt where your factory wires feeding the alternator attach - is perfectly fine.

Alternator-starter wiring harness

In addition to the cables extending to the alternator, starter, engine ground, and fender, there are wires connecting the factory fuse box, alternator, and starter by way of connectors. You can reuse those wires, pins, sockets, seals, and connectors. However, you may want to replace them completely. Below are the part numbers, which you can also find by reading the codes on the back of each connector:

• 90980-10868
  • This is the four-way connector for the factory fuse box. It connects the factory fuse box with the alternator and starter.
  • The wiring manual refers to this connector as "EA1".
  • Corsa Technic offers this connector as a highly configurable kit.
• 90980-11349
  • This is the three-way connector for the alternator.
  • Corsa Technic offers this connector as a highly configurable kit.
• 90980-11400
  • This is the one-way connector for the starter.
  • Corsa Technic offers this connector as a highly configurable kit.

Corsa Technica's inventory is truly amazing. I strongly recommend Corsa Technica.

If you choose to reuse your connectors but replace the seals, pins, and sockets then here are the parts you will need, all of which allow you to choose the wire gauge you want:

• The seals for the one-way starter connector.
• The socket terminals for the one-way starter connector.
• The seals for the four-way connector.
• The pin terminals for the four-way connector.
• The seals for the three-way alternator connector.
• The pin terminals for the three-way alternator connector.

When it comes to designing a brand new alternator-starter wiring harness, I suggest that you not use the factory wiring harness as a template. You will find the factory harness too big, particularly the connection between the fuse box and alternator. Designing a new harness is no doubt frustrating. Realize, however, that doing so will save material (i.e. $$$) and, crucially, minimize the risk of contact with the engine and-or air-intake system - both of which get hot! On that note, refer to the first section of this post for more information on wire sheathing and heat shrink.

 

Nice write up

Less the alternator how much did you spend and how long?

I have been making my own cables for years.

I have bought many things over the years from Ballenger Motorsports.

 

Thank you.

I am extremely sick at the moment with COVID so I do not have the energy to calculate the costs. More, I wonder how cost ought to be calculated anyway. Should tools (e.g. heat gun, etc.) be included?

If you are only concerned with cost of materials then links to all of the materials are provided in my OP.

Costs will vary according to material quality; however, when it comes to electronics, in my experience, you get precisely what you pay for. There is no free lunch when it comes to wiring, connectors, etc. Spend as much money as you can reasonably afford.

 

I hope you feel better !!

I was just curious I pretty much stocked up on my supplies back in 2018

i tend to give away things much to cheap!

 

OP edited to reflect new learning.

 

Hi! Thinking about fixing up my battery wires, is this jeep cables kit just an easy plug and play, all the extras you have in here are if you are upgrading your alternator? Correct?