Upgrade to 130A alternator or no?


97Ranger3.0

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Hey guys, looking for an opinion on what to do.

I've got a 1997 Ford Ranger with the 3.0 which has a 95 amp alternator from the factory. The alternator was already replaced when I bought the truck and seems to do fine. However, I've added a two speed electric fan from a 3.8 Ford Thunderbird being run with a VW temp switch and a Volvo relay as many people do. It works well and I've never had the fan kick on anything but the low speed. My air conditioning does not work currently, but I am planning on fixing it soon. So this is where my dilemma is - when I fix the AC, I plan on wiring the electric fan to run on the high speed setting at all times with the AC being on (other than if I use a manual over ride switch to shut it off if I'm cruising at highway speeds).

So what I'm wondering is, would I be pushing the limits of the 95 amp alternator if I had all of that running at the same time? If so, should I swap to a 130 amp alternator or is there anything else I can do with the 95 amp? Also, if I do need to swap to a 130 amp alternator, do I need to upgrade any of the alternator or battery wiring?

Thank you
 


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RonD

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That does sound like a good idea
Your current 95amp alternator only has 50amps at idle, its 95amp rating is at about 1,800rpms on the engine
A 130amp alternator would have 65-70amps at idle

ALL alternators are rated this way, max amp rating is when engine is at about 1,800rpms, you get about 50-60% of that rating with engine at 700-800rpm

On a 1997 you should add another wire from the B+ post on the back of alternator to the Power distribution post on the inner fender, and this wire should also use a Fusible link, 12 gauge, Ford's is a dark grey fusible link

Follow the positive battery cable to the Power distribution post(starter relay), thats where the current B+ wire is connected
You can usually see its fusible link connected there, you are just duplicating this connection for higher amp
Use same gauge wire as seen on B+ now, which should be 8-10gauge, and same type of fusible link at power post, 12gauge

Or you could change to ONE 6gauge wire and a Mega-Fuse, 175amp, Ford did this setup in later years

You could get all this at a wrecking yard, wire, fusible links or mega-fuse, used on most Ford trucks

The other 3 wires on alternator are fine, they are lower amp for voltage regulator
 
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97Ranger3.0

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Manual
That does sound like a good idea
Your current 95amp alternator only has 50amps at idle, its 95amp rating is at about 1,800rpms on the engine
A 130amp alternator would have 65-70amps at idle

ALL alternators are rated this way, max amp rating is when engine is at about 1,800rpms, you get about 50-60% of that rating with engine at 700-800rpm

On a 1997 you should add another wire from the B+ post on the back of alternator to the Power distribution post on the inner fender, and this wire should also use a Fusible link, 12 gauge, Ford's is a dark grey fusible link

Follow the positive battery cable to the Power distribution post(starter relay), thats where the current B+ wire is connected
You can usually see its fusible link connected there, you are just duplicating this connection for higher amp
Use same gauge wire as seen on B+ now, which should be 8-10gauge, and same type of fusible link at power post, 12gauge

Or you could change to ONE 6gauge wire and a Mega-Fuse, 175amp, Ford did this setup in later years

You could get all this at a wrecking yard, wire, fusible links or mega-fuse, used on most Ford trucks

The other 3 wires on alternator are fine, they are lower amp for voltage regulator
Thank you very much for the advice! I will add all this to my list to do when fixing the AC.
 


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