Big 3/5 Battery Terminal Question

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jus10inbrla

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Pretty much all of the earlier TBIs had one positive to the battery and one to the buss bar. The alternator positive goes to the buss bar too.
So should it be line side #2 battery to buss bar, load side 1/0 buss bar to alternator.

Or #2 battery to buss and 1/0 battery to alternator, with nothing between alternator/buss


Edit to add i will be putting in a 150amp fuse on the 1/0
 

Donald Mitchell

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I used stainless all thread and nuts on the side post. I also added a #2 ground to the fuel pump block off and a #6 from the firewall to the intake close to the MAF. All these hevier cables made a big difference in cranking power.
 

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PlayingWithTBI

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So should it be line side #2 battery to buss bar, load side 1/0 buss bar to alternator.

Or #2 battery to buss and 1/0 battery to alternator, with nothing between alternator/buss
Where are all of your Lights wired? Not the buss bar I would hope. I would hope you're running relays directly off the battery so, it'll help buffer the power surges when you switch stuff on/off. I'd wire the alternator to the highest point of load which, in this scenario with relays, would be the battery.

Edit to add i will be putting in a 150amp fuse on the 1/0
Depending on what Amp rating alternator you run, you'll wanna size it to that. A fusible link would be better, in industrial applications, we size the fuse/circuit breaker at least 125% of rated load/supply to eliminate nuisance outages.
 

jus10inbrla

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Where are all of your Lights wired? Not the buss bar I would hope. I would hope you're running relays directly off the battery so, it'll help buffer the power surges when you switch stuff on/off. I'd wire the alternator to the highest point of load which, in this scenario with relays, would be the battery.
I only have one 20” light bar. Its straight to battery .
Depending on what Amp rating alternator you run, you'll wanna size it to that. A fusible link would be better, in industrial applications, we size the fuse/circuit breaker at least 125% of rated load/supply to eliminate nuisance outages.
it will probably be a 160. Yea I forgot to upsize fuse. Better make it a 200.
 

Schurkey

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Grossly-oversized cables will need to be supported; in particular I'd be concerned about the stress on the lil' output stud on the alternator.

Not my cup o' tea. I think super-sizing the cables is a waste. Consider how much load each cable could see, and size appropriately for the load and the length.
 

Erik the Awful

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My method was to use Mil Spec lead battery lugs, there are 3/8th(+) and 5/16th(-) specs for the different battery post sizes.

The longer 3/8th bolt can be used with your standard 3/8th crimp wire lugs on that large wire.

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If you don't need trick, this is absolutely the way to go. Get a lug kit, a crimper, and some heat-shrink and make your own cable ends. I work on flightline equipment for the Air Force, and our equipment either gets used every day or it sits for years at a time with only an inspection every six months. These cable ends are repairable, easy to adjust and clean, and flat-out work. Our only problem with them is younger technicians tightening them down until the clamp ends touch.
 

mn_ski

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using all 1/0 cable except for #2 i think 12v to j box / 12v bus, will have;

1/0 Positive from Alt to Battery

#2 Positive Battery to 12v
bus bar

1/0 Ground Alt to Battery

1/0 Ground Chassis to Battery

1/0 Ground Enginge to Battery

1/0 Ground Frame to Battery


How are yall connecting to the battery itself ? Ive seen the 6 terminal battery tops , but reviews are hit & miss on them actually working. Any reputable source ? I had bought a 2 terminal few yrs ago for a different truck, and it came with a sleeve for negative terminal but even that wasnt small enough.

Any advice taken. Thanks in advance
I used a kit from @5vortec7 . Looking at your list I don't recall having a Alt to Battery Ground.

I did have Battery (-) to Engine and Battery (-) to Body panel fender (maybe that is what you are calling Chassis?).
Then separately I had a Frame to Body panel Fender and a seperate engine to Frame connection.

Here are the battery connections provided in the kit:
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alpinecrick

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In GM nomenclature the "buss bar" is called the Power Center.

When I upgraded my 97 I borrowed my friend's doohickey (that's not official GM nomenclature) that attaches to the battery and draws a load on the electrical system. It will draw 200+ amps. I tried the doohickey as I replaced various cables one at a time. The biggest improvement was the ground cable from the alternator bracket to the battery--which is really the only new cable rather than the replacement cables on a Big 3 upgrade.

Unless one is planning on running a boom box big enough to break glass or of course a 10k winch the monster cables don't seem to offer any more power. Number 1 or number 2 cables seem to be more than enough.

As Shurkey mentioned big cables need big support or the cable ends and the posts they are connected to are more likely to break. Especially where I live at where 15 miles of washboard Forest Service road will test every attachement--factory or add-ons.....

The strongest cable ends are homemade ones using RK copper pipe/tubing (used for commercial A/C) that have thicker walls than conventional copper pipe. Smash one end with a vise until it is ALMOST flat, fill with solder, stick the cable into the round end, fill with solder and crimp it. Grind off the square corners on the flattened end, drill the appropriate size hole for the bolt or post.
 
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