How-To: Big 3 Upgrade (Extremely Pic-Heavy)

[stadt11]

Nice write-up!

 

[elcompaLalo]

Thank you for the write-up. I can honestly tell you it has already helped me out first by explaining the Big 3 and second on bringing it to my attention how things like this may get overlooked when modding our trucks.

 

[CJ Hungus]

Very Nice write up!

 

[ScottyBoy]

When I do mine, I don't want 4 or 5 ground cables going to my battery. Wouldn't it work just as well if I ran a heavy ground to the frame, then at that same point or mounting location (using the same bolt on the frame), run one to the engine and to the body?

 

[mblouir]

Thanks for the compliments, guys. Hope it helps!


Scotty,
There are actually only two going to the battery. Same as stock for my truck, just upgraded. The engine block is grounded to the frame (green color).

You can do the frame to chassis directly, though, yes. It's essentially the same thing. It's also the one that isn't necessary, but doesn't hurt. Part of the Big "4". So really if you only do the Big 3 you will have the one going from battery negative to frame. Then the engine block is grounded to the same location on the frame. Only one left of the three is the positive to alternator.

 

[Bigredmariner]

Finally got a chance to look at the write up, nice job as usual. Thanks Matt.

 

[mblouir]

Glad to contribute.

 

[bubbatrucklover]

Just got a chance to read this.


Sucks I can't really use this though:





Good write up. Thanks for taking the time to use great detail and plenty of pics.

With a lot of people asking about this (or ones un aware of this upgrade) it's great it's a sticky.

 

[yota.coma]

nice write up!

 

[Bernie]

Glad to do it! It was fun for me and hopefully it makes this easier for others.


Two things were brought to my attention:

1. Wire Loom
2. Fuse Rating

I will be putting wire loom on all the wires---I was just running short today and it's been a long week. I wanted to put this up while I had the spare time.

I used a 250A fuse because KnuKonceptz rates their flex cable at "over 300A". Some people say match the ratings, some say you don't need a fuse, etc, etc. First of all I used a fuse to be safe. Even though power flows both ways I don't want the wire to get overloaded. I chose a 250A fuse because in the case something happens I want the fuse to blow before the cable reaches its limits. Just staying safe.

The main purpose of that fuse isn't to protect the cable, it's to protect the alternator. You want the fuse to be just slightly above the rating of the alternator so that if something starts making excessive demands on it the fuse will blow before the alternator fries.

For a stock 100 amp alternator I'd use a 125 amp fuse. On my 140 amp system I use a 150 amp breaker.