liljojo4711

i want to upgrade my electrical to 0 gauge but there are 2-3 wires coming from my positive battery terminal. what do the wires go to and how do i integrate them with the 0 gauge wiring? also, where is the wire from the alternator?

jivepepper

One goes under the front of the motor to the starter.

liljojo4711

can i just unbundle the wires and then bundle them back again? im not sure how it was done from the factory...

cliffyk

I can't envision what you are looking to accomplish, do you have some huge load you wish to power in addition to the normal loads?

I am assuming that is the case and that you will be adding a terminal/distribution block to be fed from the 0 ga. wire from the battery--if so then just connect the 2 existing wires to the distribution block.

On my '02 there are two wires from the battery + terminal--one to the starter as stated above, and one to the battery junction box (just aft of the battery). This second wire feeds the BJB and also two fusible links that recombine and connect to the generator.

Here's a link to a PDF of the battery/BJB/generator wiring...

BTW-technically it is a generator, as Ford has labeled it on the schematic.

Alternators produce AC power, generators DC, and ever since the incorporation of the diodes and regulator into the same housing as the alternator (a long time back) the assembled unit making electricty in automobiles has been technically a generator.

Oddly, we call the things you use in the aftermath of hurricanes/tornadoes/ice storms/etc. to power your toaster "generators", when the are correctly alternators--go figure...

liljojo4711

im going to add a new stereo system. about 1500 watts rms. dont want any dimming...

hpwrestler220

you're gunna go def.. i only have dimming on my system under VERY heavy loads... otherwise its pretty normal if i dont crank it up..

my friend has two Type R's in his trunk and his car dims like a mother f*cker.. good luck though. dont blow ur ear drums out

my single 12" type R is too loud for me and its de-tuned.. how much bass and loudness can you possibly want?

liljojo4711

i am going to have a single 12" and build a custom ported box and send it 1200 watts rms. then im getting some component speakers and they will be getting about 150 watts each... my mach 460 speakers in the front are blown pretty bad so i figured its time for an upgrade.

cliffyk

That's 120+ A at 12.6V. With only one battery, with the sound system at 60% to 100% output, you will have dimming--doesn't matter what size wire you run to the audio system (actually the bigger the wire the more the battery voltage will drop).

The starter draws 80-100 A, watch your lights when you crank the engine--that's what you'll see when you've got that puppy cranked up. You need one or two more batteries (preferably deep discharge) and an isolator to keep the car and audio system power supplies separate. That's how nearly all RVs are set up.

You may also want to look into a larger generator. The OEM unit is rated 110A (GT, the Mk1 and Cobra are 120A), however that is at 6000 generator pulley rpm (about 2000 engine rpm). At idle (about 2200 pulley rpm) it's a lot less at only 10A to maybe 20A. There are generators (OK, alternators) that are optimised for higher output at low rpms.

liljojo4711

i have a yellow top under the hood and the bigger the wire the voltage will not drop. im going to see what happens and if i need to ill get a HO alt...

cliffyk

The voltage at the load will always drop unless you have a perfect conductor and a 0Ω supply--however what I was referring to was that the battery voltage itself will drop further with a larger feed wire (don't ignore your grounds either) than with a smaller feed. This is because the larger feed wire will not starve the powered device as would a smaller wire--this allows the device to consume more power (current).

Since the battery has internal resistance*, the voltage at the battery terminals (and thus the voltage available to the car's other systems) will drop further as the sound system draws more power--that it will be permitted to do with larger supply wiring.

I.e. with a high-capacity, home-run, connection the sound system will "hog" the battery's capacity, at 100A load the battery voltage (fully charged) will drop in theory by 0.015Ω * 100A = 1.5V (the battery's internal resistance times the current). However the reality may be a bit more as the internal resistance climbs as load increases.

Mostly we get to ignore voltage source resistance/impedance, but when you start drawing higher loads (loads that reach 40% or more of the supply's capacity) it can become a significant factor.

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* - This is a small resistance of 0.01Ω to 0.02Ω when fully charged, that increases as charge decreases.