big 3 question(pics included)

[hrtbrk1 5,000+ posts]

no. run 1/0 non fused for your big 3
-batt to chassis

chassis to engine/*****

+batt to alt.

no fuses for teh big tree

so if i have a unibody i can ground my ***** to my unibody?

 

[NhustlaR 10+ year member]

yes, you will see a ground wire going from your transmission to your body. all youre doing in the big three is locating the three existing wires and replacing them with bigger wire. It's not rocket science. everyone makes this out to be way more complicated than it is.

 

[hrtbrk1 5,000+ posts]

oh i know what it is, i just never checked at the ****** i guess...that would have saved me time instead of trying to find a place on my engine...

 

[bubbagumper6 5,000+ posts]

Or you could just skip both of those and ground straight from chassis to your alternator bracket...It's usually just called "engine block to chassis" because it's difficult to get to the alternator on most cars but that's what that wire is for. So if your alternator is right at the front on top (like mine) you can just use one of it's mounting bolts and ground right there //content.invisioncic.com/y282845/emoticons/smile.gif.1ebc41e1811405b213edfc4622c41e27.gif

 

[Chrispy 10+ year member]

My alt is pretty much buried. Took my dad whos a mechanic and I about 2 hours to get to my alt. Cadillac. Was well worth it though.

 

[ccab 10+ year member]

sp nhustlar are you saying just run the 0 gauge from alt to bat? no fuse at all?

 

[hrtbrk1 5,000+ posts]

i should just do the Big 5

i know its prolly not gonna help, but what would it hurt //content.invisioncic.com/y282845/emoticons/smile.gif.1ebc41e1811405b213edfc4622c41e27.gif

 

[bubbagumper6 5,000+ posts]

i should just do the Big 5
i know its prolly not gonna help, but what would it hurt //content.invisioncic.com/y282845/emoticons/smile.gif.1ebc41e1811405b213edfc4622c41e27.gif

That would just be a waste, you'd have 3 wires doing the same thing...

 

[hrtbrk1 5,000+ posts]

its ok...the more the merrier //content.invisioncic.com/y282845/emoticons/smile.gif.1ebc41e1811405b213edfc4622c41e27.gif lol

 

[anibal 10+ year member]

Hope this sketch helps a little bit, this is for 2 amps, using 1/0 to a distribution block to the back then short run of 4 gauge to the amps.

 

[NhustlaR 10+ year member]

Hope this sketch helps a little bit, this is for 2 amps, using 1/0 to a distribution block to the back then short run of 4 gauge to the amps.

ehh what's that have to do with the big 3?

and sure you can fuse the alt+ to batt+ to protect your system in case of a short, but if installed properly you should not need one. I would like to see how much resistance a fuse actually adds to the wire.

 

[anibal 10+ year member]

ehh what's that have to do with the big 3?
and sure you can fuse the alt+ to batt+ to protect your system in case of a short, but if installed properly you should not need one. I would like to see how much resistance a fuse actually adds to the wire.

he had many other questions... not just "the big 3"

And about the fuse in the alt to battery wire. I guess if he does his own "car jumps" with jumper cables and assuming he knows how to do it right every time his alt will survive.

It works both ways, if the car is daily driven and he doesn't know how to jump it in case the battery drains, or the terminals are connected wrong then a fused line would be good in this case. If he has been around the block and knows what he is doing then no it is not needed.

I have done it both ways through the years, In my current car I am on my 3rd alternator. Original 70 amp died picked up a 160amp, needless to say my alt went along with my battery, It wasn't fused. Ended up with a hole under my battery from the leak. Now I had the amp rebuilt, fused the wire and added an optima.

When I upgrade from the 4 gauge to 1/0 it will not be fused.

When I have time I will take measurements of the wire with the fuse inline and without.

 

[ummduh 10+ year member]

Are you guys REALLY arguing over fusing the alt charge wire or not? REALLY?

ALWAYS fuse a power wire. ALWAYS FUSE A POWER WIRE. This is like wiring 101. If you have a power wire, you fuse it. End of discussion. Put the fuse as close to the battery as possible.

Would you rather your car burn down because you didn't?

And yes, EVERY single car sold has the factory wire fused in some way shape or form. Most cars now a days use a fusible link instead of an actual fuse.

Personally, I fuse the alt charge wire the next amp rating up from what the alt is rated at.

"If you install it correctly you don't need the fuse"..

Yea.. So, do you know exactly what is going to happen if you get into a crash? You know how and where that wire is going to move? You DON'T know exactly what is going to happen or what could happen at any given time.

Next thing you know, not only did you just get in a crash, but now your car is on fire because you didn't fuse the alt wire, and with any luck your leg is going to be pinned in the car..

Even an 8ga wire is more than capable of starting your car on fire when it shorts out.

 

[boogeyman 10+ year member]

For Those Who Refuse to Fuse:

Now let's see what will happen if excess current is passed through a small conductor. We will assume that some imaginary piece of wire (we don't want to destroy a real piece of wire) has .01 ohms of resistance (e.g. a 15 foot long piece of 8 gauge wire) and that wire is connected directly to the positive terminal of the battery (without a fuse... that should scare you). Now let's say that the other end of the wire is allowed to touch to the chassis of the vehicle (which, in most vehicles, is connected to the negative terminal of the battery). The two battery terminals are basically shorted together by the wire (through the chassis). In this situation, a very large amount of current will flow through the piece of wire.

If we wanted to calculate the current flow through the wire, we would use the Ohm's law formula I=E/R. If we use the ideal automotive battery, which is rated at 12 volts, and divide it by the resistance of the wire which is approximately .01 ohms, we get a current of 1200 amps.

I = E/R

I = 12/0.01

I = 1200 amps

Then plug the current into the formula P=I^2*R. We get:

P = I2*R

P = (1200*1200)*0.01

P = 14,400 Watts

This shows that the wire would dissipate 14,400 watts of heat which would melt the wire's insulation and more than likely ignite everything that comes in contact with the wire (fuel lines, other wires, carpet, plastic, insulation). In comparison, the largest burner on your electric stove will not put out that much heat on high!.........................................................as ummduh stated ALWAYS FUSE A POWER WIRE......END OF DICUSSION.

 

[AlterEgo99 5,000+ posts]

I've done the Big 3 and just added a second batt...EVERYTHING is fused. I don't see why one shouldn't...just common sense.

By the by, had a very slight alternator whine before adding the second batt under the hood, since adding the second batt, no more whine at all AND no headlight dimming. //content.invisioncic.com/y282845/emoticons/biggrin.gif.d71a5d36fcbab170f2364c9f2e3946cb.gif