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the myth
6th January 2007, 09:57 AM
many do not know this info so i decided to go ahead and make a post out of it



As many of you know, upgrading the "Big 3" wires in your engine compartment can lower the overall resistance of your entire electrical system. The effects of the lower resistance are typically:

1) Reduced dimming and smaller voltage drops
2) More stable voltage and better current flow
3) Less strain on your vehicle's charging system

So for those of you looking for a cheap and easy way to upgrade your system and help out your electrical system without adding a high output alternator or an aftermarket battery, this is the modification for you. If you have heavy dimming or are getting large voltage drops during loud bass hits, but you don't have the money to spend on a high output alternator or a battery, upgrading your vehicle's "Big 3" will usually help to reduce and sometimes even eliminate the problems. So without further ado, the "Big 3" wires are:

1) Battery negative to chassis
2) Alternator to battery positive
3) Chassis to engine

Now, I suppose it would help if I explained what each of these wires does, and to do that I would like to paraphrase an explanation by IMTfox from a while ago: Think of your vehicle's charging system as two different circuits, one consisting of your amplifier and your battery, and the other consisting of your alternator and your battery. The current in your electrical system flows from your positive battery terminal to your amp, from your amp's ground to the chassis, and then from the chassis back to the negative battery terminal. But how does it get to the positive terminal in the first place? That's where the alternator comes in. Current in the second circuit flows from your alternator's positive post to the battery's positive terminal, then from the battery's negative terminal to the chassis, and from the chassis back to the block, which happens to be the grounding point for your alternator.

So, from your battery, you have the power wire going to the power terminal on your amplifier and then your amplifier is grounded to the chassis of the vehicle. From here the current needs a way to get back to the negative battery terminal, and that way is through the first of the "Big 3," the battery negative to chassis wire. Upgrading this wire will "upgrade" the circuit between your battery and your amp by giving the current a larger path to flow through to get back to the battery.

Now, think of your alternator as the battery and your battery as the amp. From the positive post on your alternator, you have the second of the "Big 3," the alternator to battery positive wire supplying "power" to your battery. From there the battery, just like your amp, is grounded to the chassis through the wire mentioned in the previous paragraph. Again, the current needs a way to get from the chassis back to the alternator's "negative terminal" and that way is through the last of the "Big 3," the chassis to engine wire. Since your alternator is most likely mounted to your engine block using a metal or conductive mounting bracket, you can simply add your new wire from the chassis to one of the mounting posts for the alternator. Upgrading these two wires will "upgrade" the circuit between your alternator and your battery, again giving the current a larger path to flow through.

TraPStaR
9th January 2007, 12:14 PM
i was wondering if there was a Step by Step guide or something that you could post. I might want to do this, but i dont want to fuck it up and all... im good with wiring but the steps might be a little more complicated then i am taking it.

thx in advance

the myth
11th January 2007, 09:58 AM
i was wondering if there was a Step by Step guide or something that you could post. I might want to do this, but i dont want to fuck it up and all... im good with wiring but the steps might be a little more complicated then i am taking it.

thx in advance

it would be diffrent on every car

the main thing i have found is they run your Alternator to battery positive
in a 8-12 gauge depending on make
you will need to add atleast a 4 gauge
0 gauge if you could

the hardest part is makeing a wire fit the alt. postive hook up
try leaveing factroy aswell. does not always work well.but 2 will always be better then 1

after that add extra ground from Chassis to engine and then Battery negative to chassis(0 gauge)

and yes i said add wires
do not replace
leave factroy grounds and alt. power wire if possible
electric will alway take the path of least resisted


i have done this to cars and it has help none.
but on cars that have major volt drops it will help more then a power cap forsure
i did this on dpg ride and before his volts was droping to 9.8-10.2 on bass drops afterwards the lowest i could get it to drop was 12.3 but for the most part it stayed well above 13.1