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Electrical 2G Alternator to 3G Alternator Upgrade (upper bolt size)

  • Thread starter Thread starter 88VertFox
  • Start date Start date May 17, 2023
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    3g upgrade alternator bolt
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88VertFox

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Mar 19, 2022
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May 17, 2023
#1
  • May 17, 2023
  • #1
I have an 88 5.0 Fox and I’m upgrading the alternator to the 130A 3G version. The new alternator is threaded for the upper bolt. What size bolt do I need for this?
 

AeroCoupe

lube between the nut and the face. I know my lubes
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#2
  • May 17, 2023
  • #2
Good question. Could be metric or standard so unless you have a tap and die kit I would take the alternator down to Home Depot, Lowes, or a good hardware store and you should be able to find one that fits. Both of mine did not come threaded so I want to say I just made them 7/16-14.
 

Noobz347

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#3
  • May 17, 2023
  • #3

3G Alternator Fox Upgrade

Preface: When the following procedure is complete, the ORANGE/BLACK factory alternator wire WILL NOT BE USED. Whether you cut that connector off or just leave it hanging is up to you (I prefer to just leave it tied up out of the way). Using...
stangnet.com
 
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limp

wrap a little cheese around it and its a done
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#4
  • May 18, 2023
  • #4
Is it worthwhile to upgrade this 10 ga wire to a larger size if your using the stock alternator?
 

AeroCoupe

lube between the nut and the face. I know my lubes
Founding Member
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#5
  • May 18, 2023
  • #5
If you have additional load on the system like an aftermarket ignition box, stereo, electric fan, etc. I would say yes. I would just go ahead and put a 4 gas in that way if you ever swap to a 3G then its already there. I just grabbed this off of one of the many sites that provided wire size and maximum amps:

Chassis wiring:
10 ga - 55A
8 ga - 73A
4 ga - 135A

Some are even more conservative than this but you can see the 10 ga is a joke.
 
Reactions: 90sickfox, General karthief and limp

Mustang5L5

That is…until I whipped out my Bissell
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#6
  • May 19, 2023
  • #6
The two 10G's actually splice together in the harness into a single 10G wire.


Look up the rated ampacity for 10G wire in a hot environment. Once you see what it is (less than 75A for sure), you'll upgrade. Even 4G is just barely acceptable for a 130A alt, which is why i cringe when folks are installing a 200A alt, with 4G wire and installing a 200A fuse. With 4G you should really fuse for 100-120A.


"But LMR sells the 200A kit with 4G wire! "

https://lmr.com/item/SVE-17046K200BK/mustang-sve-black-200-amp-alternator-and-bracket-kit-86-93

 
Reactions: General karthief

Mustang5L5

That is…until I whipped out my Bissell
Mod Dude
Feb 18, 2001
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May 21, 2023
#7
  • May 21, 2023
  • #7
Btw. Here’s what happens when you use the #10 wires with a 3g alt


 
Reactions: rednotch

rednotch

I'd like to remain having one chocolate starfish
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#8
  • May 21, 2023
  • #8
Lmfao the you see in those Facebook groups...
 
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