OK guys need some help. I upgraded my Alt to a 120 Jag Alt and swapped my
battery and air box. Now its time to wire it all up. I have searched the forms
and cannot find info on the BIG 3 when done in conjunction with the air/batt
swap.

everyone says you need to put a 120-150 in line fuse from the Alt the the Batt so i went and purchased that but im having a hard time trying to figure out where the put it and keep the system working correctly. Im trying to keep from running tons of #2 cable all over my truck. I have some pictures below showing the stock setup and then how i would like to set it up. I need to know if it would work. Thank you for you help. PS Sorry for the pics all i had at work was Paint.

Thank you for any help.


STOCK SETUP (where are the wires in question going? Do they have to be connected back to the battery like they are stock?





I would like to run everything like this if the wires in question dont have to run back to battery.. Will this work?




If the previous wont work will taking the 80 out completely and replacing it with the 120 work?

 

I'm basically in the middle of the same thing, except I'm not doing the big 3, I had to relocate the battery because of the 3.4 swap; I'm doing the same thing as your middle picture (your first of 2 options). Mine is a '91 4Runner v6 so there may be some subtle differences but it should be close enough.

There is a white wire (about 8-10 gauge) that goes from the POS battery terminal to one side of the 80A fuse; which is the "ALT" (alternator) fuse. The end in the fuse box is crimped to a large copper mounting tab, I cut that crimp connection off with a dremel, then ran new 8GA wire from the battery (now on the driver side) to a new crimp-on ring terminal that I screwed into that copper tab. I mounted a 160A fuse to the driver side fender well and connected one side to the alternator and the other to the battery.

Take a look at the following 2 pages from the EWD, spend some time tracing everything out on paper compare that to what things look like in your truck.
http://www.ncttora.com/FSM/1990-1995...i/charging.pdf
http://www.ncttora.com/FSM/1990-1995...i/pwrsourc.pdf

And just a heads up, that alternator is rated to produce 120A you want a fuse much larger than that, otherwise you'll blow that fuse continuously with a heavy load. I'd go with a 200A myself; I'm running a rebuilt stock 3.4L alternator (I had Boyle Future Tech do it without any upgrades) and its rated at 90A, but I'm using a 160A fuse. If you blow that fuse, you lose power everywhere, and you're stuck until you can replace it.

 

just run a new wire to the alt and keep the factory one

 

I also kept all of the factory wires on the alternator and ran new positives from the battery to the alt, battery to starter and from the battery to the fuse box. I used a Stinger (car audio) marine grade circuit breaker and mounted it to the innner fender (has tabs for mounting).

I made all new ground straps as well.

 

just some extra info, where i learned how to do it.

http://www.caraudio.com/forums/wirin...-3-thread.html