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Alternator upgrade question.

TexasNomad

FTFS Designated DRINKER!
Hey guys I want to up my amperage on my 79 5.0 I have a 75amp on there now and I want to go up to at lest a 140AMP.
I have a lot of extras on my truck like a big stereo electric fan and fuel pump.
Can I just swap out Alternators or is there more then that??
Thanks allot :)
 

Skandocious

Post Whores Make Me Sick
19,076
655
California
Depends on what you're doing... You're going to want to upgrade to a 3G alternator. You can tell which is 3G cuz it'll have an internal fan.

2G external fan style:
1789L.jpg



3G internal fan style:
pa-1619.jpeg




You'll most likely need to change your alternator harness, and for sure upgrade your charge cable so it won't melt with the added amperage. You can get EVERYTHING you need at RJM Injection.

Alternators:
http://rjminjectiontech.com/?p=6

Alternator accessories/parts:
http://rjminjectiontech.com/?p=7


Instructions for the 2G-3G upgrade:
http://fordfuelinjection.com/?p=75
 

radialarm

Clown of Death!
Those sites Chris gave you are all great. Just do your homework, so you don't have any problems.
 

radialarm

Clown of Death!

TexasNomad

FTFS Designated DRINKER!
HOw did it cost you 40 bucks those alternators were over a 100 bucks.
I have a 1979 it dose not use 3g plug and harness I would have to change out tons of wiring and it would end up costing twice the amount of this one from Jegs.
 

radialarm

Clown of Death!
HOw did it cost you 40 bucks those alternators were over a 100 bucks.
I have a 1979 it dose not use 3g plug and harness I would have to change out tons of wiring and it would end up costing twice the amount of this one from Jegs.

Those sites Chris gave you have an adapter harness so you dont have to change a lot.

You can get an alternator at a junkyard cheap $20.00 just check around.

You shouldn't need a 140amp as a factory 130 should cover it.

Read the alternator files at Ford fuel injection or RJM.
Lots of good info for free.
 

TexasNomad

FTFS Designated DRINKER!
Suit yourself smilieeatndrink
What..
7″ Pivot 160Amp 3G $125.00
$10 for the pully
$25.00 for the Reg
Then $40 for the wire upgrade
Add shipping and your pushing over 200 or I can pay 207.98 for some thing I can bolt up and plug in.
it's the same price with less work I don't see your reasoning on this man.
 

Skandocious

Post Whores Make Me Sick
19,076
655
California
What..
7″ Pivot 160Amp 3G $125.00
$10 for the pully
$25.00 for the Reg
Then $40 for the wire upgrade
Add shipping and your pushing over 200 or I can pay 207.98 for some thing I can bolt up and plug in.
it's the same price with less work I don't see your reasoning on this man.
That's if you buy everything new... The junkyard is a goldmine YelloThumbUp

I only paid $35 for all the parts that I needed, +$40 for the charge cable. Read my alternator swap thread.
 

TexasNomad

FTFS Designated DRINKER!
that was a good thread chris.
I'll call around on Monday and see what I can find and if I can find one for that cheap I will think about doing this but to tell you the truth :D I am kinda lazy and dont really know if I want to do that much work for a used Alt....
 
WARNING...
do NOT install and alternator above 100 amps,you don't really need it and In most cases the wiring can't handle it.

Just get yourself the 100 amp alt out of a FULLY loaded E-series van.Get yourself an Deep cycle RV battery to run the stereo

Oh ..and upgrade the Voltage reg as well.

All parts are NOT created equal.
 

Skandocious

Post Whores Make Me Sick
19,076
655
California
WARNING...
do NOT install and alternator above 100 amps,you don't really need it and In most cases the wiring can't handle it.
Dennis... Just exactly which "wiring" are you talking about? The only wire that will experience added amperage is the charge cable, and we've already told him that he'll need to upgrade to a bigger charge cable.
 

TexasNomad

FTFS Designated DRINKER!
WARNING...
do NOT install and alternator above 100 amps,you don't really need it and In most cases the wiring can't handle it.

Just get yourself the 100 amp alt out of a FULLY loaded E-series van.Get yourself an Deep cycle RV battery to run the stereo

Oh ..and upgrade the Voltage reg as well.

All parts are NOT created equal.
I have a deep cycle bat..
and what year of van would be good to get.
The reason I want a stronger Alt is when I'm sitting at a stoplight and turn my blinker on I can hear my fan and fuel pump surge every time the Blinker flashes.
 

radialarm

Clown of Death!
The reason I want a stronger Alt is when I'm sitting at a stoplight and turn my blinker on I can hear my fan and fuel pump surge every time the Blinker flashes.

You don't have enoghh amps if it does that.
 

radialarm

Clown of Death!
I found an 130 amp 3g alt in a mustang that has mounting holes very much like those on most 2g mounts.

I think it was off about a 98 model.

Just look around the junkyards a see what you can find.
 

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