3fe - Tundra Alternator Mod
- Thread starter M32H32is
- Start date
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LOL. You should trust me more when it comes to LSD questions 
OK, so Cliff got my OEM alternator and sends me an email saying that he made a mistake. The 80 amp units with the external fan (1991 and early 1992 FJ80) are NOT upgradeable. So I spent $25 in shipping costs for nothing. Oh well...
So Jon....
I was following the thread in hopes of doing this upgrade and my original question was "do I have an 80amp or 90amp Alt?", but after following this thread it seems that my 1991 would have come with an 80amp.
I've been experiencing dimming headlights when any other electrical device is drawing amperage (ie. turn signals, radio, wipers, etc) and I don't think its charging my battery very well either.
What are my '91 3FE upgrade options? Just moving to a 90amp? Also, how can I confirm that I have an 80amp and that the PO has not already changed it to a 90amp?
I was following the thread in hopes of doing this upgrade and my original question was "do I have an 80amp or 90amp Alt?", but after following this thread it seems that my 1991 would have come with an 80amp.
I've been experiencing dimming headlights when any other electrical device is drawing amperage (ie. turn signals, radio, wipers, etc) and I don't think its charging my battery very well either.
What are my '91 3FE upgrade options? Just moving to a 90amp? Also, how can I confirm that I have an 80amp and that the PO has not already changed it to a 90amp?
why is it that those can't be modified??
Not sure what the choices are just yet. I really don't think the Tundra unit will fit with the limited real estate.
The 80 amp alternator has the cooling fan mounted behind the pulley. The 90 amp unit has the fan internal to the case.
The picture shows an 80 amp unit from a 1991.
I didn't think it was upgradeable. Lots of soldering involved with the 80 amp. The 90 amp is upgradeable as with the one in my ride. Only draw back is finding the correct brackets or modding the stock bracket for the 80 amp to fit the 90 amp. I went with the original 90 amp bracket. Boyles Technology did a killer job rebuilding my 90amp. Been working strong since installed.
The 90 amp units are available at around $50-$80 used and there are plenty of them. Search car-part.com. It's one of the best parts sources out there.
What Tundra alternator (year/motor) is commonly used for this? I see 6 different ones available.
- Thread starter
- #31
I was wrong ab the Tundra alt mod being a 3fe thing. Photoman's brackets were for the 1fz crowd. Just like everything else
I know Photoman's kit is for the 1FZ. He was working on a 3FE kit as well, but decided to abandon it. I went back over that thread and there is little clearance between the Tundra unit case and the exhaust manifold. This just doesn't seem like a good idea to me.
Since 90 amp alternators are readily available and can be rebuilt easily, that seems like the logical choice for an "almost" bolt in 3FE upgrade. What I need is a better understanding of the mounting differences and adjuster bracket.
Does anyone have pictures comparing the 2? Since my smog pump has been replaced with a York, I may still have some fitment issues.
Since 90 amp alternators are readily available and can be rebuilt easily, that seems like the logical choice for an "almost" bolt in 3FE upgrade. What I need is a better understanding of the mounting differences and adjuster bracket.
Does anyone have pictures comparing the 2? Since my smog pump has been replaced with a York, I may still have some fitment issues.
- Thread starter
- #33
^brings up another dynamic:
I plan to desmog as well. If we remove the air pump as you have done, the creates a TON of useable space.
With that out of the way, surely there's an alternator that would fill the void nicely.
I plan to desmog as well. If we remove the air pump as you have done, the creates a TON of useable space.
With that out of the way, surely there's an alternator that would fill the void nicely.
You would need to put the new alternator in place of the smog pump using those mounts. A good possibility, but not for me. It would involve a fair bit of fabrication, but if you have the skills/tools/time you should go for it.
This link answers your questions...
https://forum.ih8mud.com/80-series-tech/375278-3fe-90-amp-upgrade-round-1-failed.html
https://forum.ih8mud.com/80-series-tech/375278-3fe-90-amp-upgrade-round-1-failed.html
Which route did you take with the brackets? Did you go OEM or did you grind down the case? What about clearance?
Went OEM....
- Thread starter
- #39
Details?
ordered my parts includiung brackets through cruiserparts.net years ago. had it delivered directly to Boyles Technology. Boyles called me when it arrived and told me condition. it was workable. recieved it from them about a week later. Alternator looked like new!
here is their contact info,
Boyle Future Technology
12325 Locksley Lane, Auburn, CA 95602
phone: (530) 888-6290
brackets were pretty dirty, took them to a friend with a blast cabinent and his wife worked over the brackets in her spare time. looked like new - coated them with some fresh primer and paint, removed all my brackets, installed the new brackets- used the same belts....
oh yeah, forgot to mention- I had already upgraded my wiring from battery to starter/ battery to alternator and all ground cables previous to install...
during install, I went to dual battery setup utilizing the hellroaring battery isolator system. it was a ton of work for a weekend project.
here is their contact info,
Boyle Future Technology
12325 Locksley Lane, Auburn, CA 95602
phone: (530) 888-6290
brackets were pretty dirty, took them to a friend with a blast cabinent and his wife worked over the brackets in her spare time. looked like new - coated them with some fresh primer and paint, removed all my brackets, installed the new brackets- used the same belts....
oh yeah, forgot to mention- I had already upgraded my wiring from battery to starter/ battery to alternator and all ground cables previous to install...
during install, I went to dual battery setup utilizing the hellroaring battery isolator system. it was a ton of work for a weekend project.