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Alright, so i was just pointed out that my battery ground is a measily 8 gauge wire, while my battery positive terminal feeds 3 amps with 3x4 gauge wires, but since my amps have their own grounding terminals ( 3x 4 gauge grounds ), do i need to provide a better ground for my battery ?

If this is indeed something i have missed and my battery ground was wrong, what potential problems might this cause/have caused ?
 

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think about it, you have (3) 4 ga wires feeding electrons in and only (1) 8 ga wire for them to come back to. I would upgrade it to a 4ga as well. (and leave the 8ga there too)
 

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think about it, you have (3) 4 ga wires feeding electrons in and only (1) 8 ga wire for them to come back to. I would upgrade it to a 4ga as well. (and leave the 8ga there too)
Actually, that's backwards. The electrons flow from negative to positive. He's only feeding them into the chassis ground (and, subsequently, the amps) with an 8-AWG cable. Upgrade that battery ground!
 

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NO, you dont even need a ground, or even a battery for that matter....

OK OK, just kidding... of course the ground is IMPORTANT.... upgrade!
 

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Ground cable should be thicker then power cables. Thicker cable lower resistance and allow battery to operate more efficient.
Alternator cant supply all amperes at every moment.
 

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That is correct, ground needs to be equal or LARGER then your power wire.
 

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do your amp grounds return to the battery negative or go to the car body? If its the car body then definately upgrade to the largest possible. If your amp grounds go to the battery then its not as important however still worth doing. My battery is under the back seat so i ground my amps straight to the battery, however, i noticed the car ran a little smoother after upgrading the main ground to 0 gauge.
 

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I use redundant grounds on my GN. If one fails, there are several other paths for flow for any given failure scenario. Always a good idea on an older car. However the ground from the battery to chassis is likely very short. I agree that it wouldn't hurt to upgrade but I feel that some treat it as if it's an 8ga wire running from the battery 20' to the trunk which it isn't'.

Some cars have more grounding than meets the eye. The main one might be 8ga but there could be redundancy somewhere. Still to my disbelief, my friend's 951 Porsche runs just fine when you disconnect both the positive and negative terminals of the battery. I know cars will run with the positive disconnected but I've never seen one continue to run with the negative disconnected. Obviously there are grounds elsewhere on the car. And yes, I know it's a bad idea to run the car without the battery in the loop.
 

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You should upgrade, and if you're going to do it you might as well upgrade it with 1/0. It will take the same amount of time and only cost you the difference in wire. There really just isn't a reason not to. I would upgrade the wire that runs from the alternator to your battery to 1/0 as well while you're at it.
 

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Actually, that's backwards. The electrons flow from negative to positive. He's only feeding them into the chassis ground (and, subsequently, the amps) with an 8-AWG cable. Upgrade that battery ground!
ok, lets argue sematics. I know that technically electrons flow away from the negative and towards the positive. how does this change my advise one little tiny bit?
 

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Still to my disbelief, my friend's 951 Porsche runs just fine when you disconnect both the positive and negative terminals of the battery. I know cars will run with the positive disconnected but I've never seen one continue to run with the negative disconnected. Obviously there are grounds elsewhere on the car. And yes, I know it's a bad idea to run the car without the battery in the loop.
my '81 rabbit diesel would do that too ;)
 

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While I would have loved to see Chad's response :D, I guess I will live un-humored.

If the 8 gauge cable that goes from the battery's negative post to the chassis and is under a foot long, odds are, you are fine. The capacity of wire is not only based on gauge but on the length of the wire run. in other words, the shorter the run the higher the capacity. If the only way to complete the electrical circuit was a 15 foot run of 8 gauge and your draw was over the rated capacity, then yes upgrade. As an example, look at the element in a fuse. Look how much current capacity a tiny little piece of copper has before the resistance causes it to heat up and separate.

Now it may help to add another piece of cable to reduce voltage drop. The chassis, while definitely easy to attach to, is less than ideal an a conductor compared to copper or even CCA. It's used because for the most part, convenient and because as the common point for car electronics it makes the most sense. Add in a huge current draw like high powered audio and now in my opinion, it makes sense to supplement to reduce voltage drop.

Take a spare piece of power cable and temporarily add it to the battery cable. Use a DMM to see if your voltage drop changes at the amps. it's an easy check. Also if your car is older, replacing may improve based on the oxidation of the OEM ground.

For disclosure, I like a bit of overkill. I ran a dedicated negative run from the negative all the way back to the trunk. I gained a half of a volt due to the decrease in resistance.
 
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