Alternator Wiring Upgrade

JMGlasgow

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Is it necessary to upgrade the alternator wiring on a stock alternator with stock electronics? I've read of fires happening as a result of the wiring being too small.

I have no intentions of adding an electric fan, higher output stereo, bigger fuel pump, etc.
 
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imp

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Is it necessary to upgrade the alternator wiring on a stock alternator with stock electronics? I've read of fires happening as a result of the wiring being too small.

I have no intentions of adding an electric fan, higher output stereo, bigger fuel pump, etc.
There should be absolutely no need to upgrade any wiring in the charge/power circuitry beyond what the maker installed, given no add-ons/minimal add-ons. How many vehicle fires have you driven by lately involving every-day vehicles? We've seen PLENTY of R-Vs up in smoke, never a car. See, not intending to "knock" "remanufacturers", but many R-Vs are purchased from the basic maker of the frame/body/driveline, then built to accommodate the whims of the "snowbirds'. Everyone builds with profit as the motivator.

Case in point. I recently bought a 23 year old Mustang '94GT, 5.0L HO 5-speed. It's alternator has a huge fat wire feeding across to the main tie-point for battery and vehicle power. #4 wire, I think. That's almost like a welding cable! Ford put that there. How could it be "upgraded"? Made BIGGER, not smaller, of course. The gain? Very little. The possible loss? Maybe plenty. How many guys "upgrading" wiring for a living TRULY understand electricity, do you think? Likely, none, or very damn few. Entrust your vehicle's integrity to a Charlatan? Not me.

(emboldened). Sure, fires are sensationalized, but for what reason? Sell you something that might help you, but might not.

.......stock alternator with stock electronics?...... By this I think you mean non-power gobbling acoustics, huge amplifiers, and such for sound systems? Yes, some of the sound installations favored today require special consideration for suitability of power supply. Why they want them eludes me, but whom am I to disagree?

If you have an original, unmolested Ford product, IMO, you have nothing to worry about along the lines of your original question. imp
 

General karthief

wonder how much it would cost to ship you a pair
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Ok, not sure what years were effected, I would say any 87 thru 93 fox should be checked for damage at the big alternator plug, there is/was a problem with them catching fire I think because the plug was defective in some way, I'm not sure. I did have this happen to my 89 gt, no damage, just a bunch of smoke from under the hood, now everytime 'the girl on the other end of the couch' gets in that car she will ask 'is it going to catch fire again?' I have to fight the urge to slap her, alas, I just smile and say 'well you could walk' :jester:
Oh, and the gt's have a problem when using the fog lights but there is a writeup on that fix in the 5.0 tech/how to threads.
Other than those two things the only problem would be smoking in a hatchback with the windows up and a gas can in the back :doh:
 
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Noobz347

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There should be absolutely no need to upgrade any wiring in the charge/power circuitry beyond what the maker installed, given no add-ons/minimal add-ons.
This is patently untrue of a Fox Mustang. The 80 amp alternator and undersized wiring in Fox Mustangs was a hazard from the start. Now, the newest Fox is 24 years old. :(

Is it necessary to upgrade the alternator wiring on a stock alternator with stock electronics? I've read of fires happening as a result of the wiring being too small.

I have no intentions of adding an electric fan, higher output stereo, bigger fuel pump, etc.
No Fox Mustang is complete without a 100 amp or higher alternator upgrade and associated 4 gauge wiring upgrade and fuse.

If you have ever seen:

lights dim at night with the turn signal on or changes in air-conditioning controls
had slow cranking after short runs
or seem to eat up batteries in short order

then it's likely you need moah powah

Our alts are junk and barely adequate. A 3G alt upgrade is easy and relatively inexpensive. It will also charge the battery at idle (our stock alts will not).

Alternators out of the way and as Karthief mentioned, the wiring and harness going into our 2G alts is inadequate and will not bear the full load of the alternator for very long. Even if sticking with the stock 2G alt, an additional supply wire from the alternator to the positive side of the starter solenoid (fused of course) is always a good idea and will prevent the situation you describe in your initial post.
 
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jrichker

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This is patently untrue of a Fox Mustang. The 80 amp alternator and undersized wiring in Fox Mustangs was a hazard from the start. Now, the newest Fox is 24 years old. :(



No Fox Mustang is complete without a 100 amp or higher alternator upgrade and associated 4 gauge wiring upgrade and fuse.

If you have ever seen:

lights dim at night with the turn signal on or changes in air-conditioning controls
had slow cranking after short runs
or seem to eat up batteries in short order

then it's likely you need moah powah

Our alts are junk and barely adequate. A 3G alt upgrade is easy and relatively inexpensive. It will also charge the battery at idle (our stock alts will not).

Alternators out of the way and as Karthief mentioned, the wiring and harness going into our 2G alts is inadequate and will not bear the full load of the alternator for very long. Even if sticking with the stock 2G alt, an additional supply wire from the alternator to the positive side of the starter solenoid (fused of course) is always a good idea and will prevent the situation you describe in your initial post.
You are 100% correct; here's the math to prove it...


Figure this:
Ignition system & computer = 12 amps
Fuel pump = 12 amps
Exterior lights = 15 amps
Fan (heater or A/C) = 15 amps (can run between 5-25 amps depending on setting)
Radio & instruments = 10 amps
Wipers = 10 amps
Rear window defroster = 5 amps (optional, not found on most southern fox mustangs unless the car moved down with the snowbird owner…)

That's grand total of 79 amps from a 65 amp alternator. Talk about overdrawn at the bank!
 
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