TheSamba.com :: View topic - 110 amp alternator upgrade for your Subaru conversion CHEAP

Thu Jun 04, 2015 7:53 am

I am very interested in doing this. I eventually plan on putting in a winch and while I don't plan to use it a whole lot, I do want to have it ready for when I do need it. I have a fairly large house battery ~200 ah that will run a fridge, propex, some led lights and a few other accessories plugged in, like laptop, phone etc.

Does anyone have any suggestions on if I should go with the 110 or the 130 Amp alt with this use case?

Thu Aug 20, 2015 5:52 pm

i just stumbled onto this Mod and I am super interested in doing this. I wish there was a pictorial guide of how to do this install. Sometimes it sucks being a visual learner.

Thu Aug 20, 2015 6:13 pm

stockypeasant wrote: i just stumbled onto this Mod and I am super interested in doing this. I wish there was a pictorial guide of how to do this install. Sometimes it sucks being a visual learner.
If you need help, let me know. Youll need both the alternator and the pigtail first.

Thu Aug 20, 2015 6:16 pm

I will gladly be messaging you when I get to that point in my 1986 2WD Westy -EJ22 (90-94) conversion. Alternator was a close second to starter upgrade for me.

Thanks again, kalispell!!!

kalispell365 wrote: stockypeasant wrote: i just stumbled onto this Mod and I am super interested in doing this. I wish there was a pictorial guide of how to do this install. Sometimes it sucks being a visual learner.
If you need help, let me know. Youll need both the alternator and the pigtail first.

Fri Apr 01, 2016 6:28 pm

Got a 12,000lb winch ready. Decided to make the 130 amp plunge, with a 2010+ Tribeca or Legacy Turbo alternator, as mentioned on page 1. Used on EBay for about $70, shipped. I thought I'd add some comparison photos. The pictures may not exactly show the differences, but the 130 amp alternator is definitely beefier:

Part number:

It's a tight fit, especially up against the hose coming from the TB. It's a five rib pulley, and I found that the outermost position lined up best with the other pulleys.

Sat Apr 02, 2016 10:35 am

Forthwithtx wrote: Got a 12,000lb winch ready. Decided to make the 130 amp plunge....

Forthwithtx FWIW I have a 12,000 lb winch. It's remote, on a "2-inch receiver mount". I carried a separate battery and ran it off that battery. I winched a huge log out of the woods, ran it a lot, on long, pretty hard pulls. So hard that I had to add a snatch-block pulley. All that work and the battery still had 12.6 volts at the end of the day.

I think you'd have to be REALLY stuck, to run your battery down. Any alternator puts out 80, 90 Amps ----> and can a battery ever accept more than 50A anyway? What exactly is the benefit you are getting from the larger alternator? It allows use of a substandard battery I suppose. Or hours of Horrific (really fun) winching operations.

Sat Apr 02, 2016 11:36 am

I follow the Tim Allen approach to upgrades. =P~ A 110 Amp, or even an 80 Amp alternator would have cost me about the same.

Sat Apr 02, 2016 11:41 am

Well if I had to change an alternator I'd choose the bigger one too as it MAY put out more at idle. But they all put out more than the battery can accept while driving. However if you had multiple HONKIN' off road lights (back in the days before LEDs) then I can see the NEED for a bigger alternator.

Sat Dec 02, 2017 10:51 am

I am seeing a lot of references to how much power a battery can accept when charging. This all changes when using lithium batteries, LifePO4. These battery can accept a hugh amount of current when charging. Our Subaru alternator is rated at 130amps, I regularly see charging rates over 100 amps at 14+ volts on a 160ah combined battery bank.

Sat Dec 02, 2017 12:05 pm

dgbeatty wrote: I am seeing a lot of references to how much power a battery can accept when charging. This all changes when using lithium batteries, LifePO4. These battery can accept a hugh amount of current when charging. Our Subaru alternator is rated at 130amps, I regularly see charging rates over 100 amps at 14+ volts on a 160ah combined battery bank.

Good to know. Is this rate linear? I know with regular batteries after the innitial rush rate tapers down.

Sat Dec 02, 2017 12:49 pm

It does taper off as the batteries nears a full charge, at around 80%. Interestingly the charge rate starts off at a much lower rate and gradually climbs to it's maximum after a few minutes. The batteries are protected and controlled by BMS modules. A simple readout via a NASA BM-1 compact meter. I am considering adding a BM-2 compact to monitor two of the banks separately.
We currently have two hundred watts of solar on the roof and additional two hundred watts portable in case of extended cloudy weather. They are controlled by a programmable MPPT that is pushed to the limit due to size constraints.

Sat Dec 02, 2017 12:52 pm

IMHO if a winch is running your battery low - your battery's no good. Or perhaps you are REALLY stuck.

dgbeatty wrote: I am seeing a lot of references to how much power a battery can accept when charging.

Does anyone know how many amps a normal lead-acid car battery normally accepts? I bet it's something like 20-40 amps. Which a 95 Amp alternator already exceeds by a longshot.

I'm interested to compare how many amps 95A and 130A alternator put out at idle, ----- to recharge the house battery quick as possible (without moving the van).

Sat Dec 02, 2017 1:18 pm

Now you have asked a complex question. Some of the best and simplest answer can found here. http://tinyurl.com/d577nsj . It will take more than one reading and a bit of thought.
Basically you are limited by voltage and this varies depending on the state of charge "SOC" The vast vast majority of automobile batteries are never fully charged and thus their life is shortened. Long haul trucks and other machinery that regularly operate for eight or more hours at a time and are well maintained do have fully charged batteries. It simply takes nearly 20 hours to fully charge a lead acid battery.
Almost forgot. Our 130 amp Subaru alternator produces in the 60-70 amp range at 800rpm depending on temperature. More when cold, less when hot.

Sat Dec 02, 2017 1:51 pm

dgbeatty wrote: It simply takes nearly 20 hours to fully charge a lead acid battery.

A 2A charger would charge a standard 40AH Vanagon battery from 0% - 100% in 20 hours (ignoring some details but just showing "the basic math"). Or from 50% to 100% in 10 hours.

dgbeatty wrote: Our 130 amp Subaru alternator produces in the 60-70 amp range at 800rpm depending on temperature. More when cold, less when hot.

Thanks for that. Prob need at least two hungry batteries to accept 60-70 amps (if Lead-acid).

If a 95A alternator puts out about 45-50A at at idle, it's probably putting out as much as (one) battery can accept, exceeding its capacity even in the battery's hungriest state. Where most other times it will accept substantially less. Thus not likely to see any improvement with a bigger alternator.

BTW I am not knocking the bigger alternator. If I had a 95A on the van and a 130A on the bench I’d install the 130. Then I’d add a 2nd house battery.

Anybody know how many amps alternator came on a 2007 Subaru Impreza 2.5 i-active?

Sat Dec 02, 2017 2:28 pm

dgbeatty wrote: It does taper off as the batteries nears a full charge, at around 80%. Interestingly the charge rate starts off at a much lower rate and gradually climbs to it's maximum after a few minutes. The batteries are protected and controlled by BMS modules. A simple readout via a NASA BM-1 compact meter. I am considering adding a BM-2 compact to monitor two of the banks separately.
We currently have two hundred watts of solar on the roof and additional two hundred watts portable in case of extended cloudy weather. They are controlled by a programmable MPPT that is pushed to the limit due to size constraints.
Dgbeatty,

I would be Interesses in your Setup. Any possibility to Share Pics and Wiring Diagramm? BOM?

Peb

Sat Dec 02, 2017 2:42 pm

Your thinking is good on the alternator output but your math is fuzzy on the 2amp charger. Hook up a volt meter and start charging the battery. Measure and write down your results each hour. It you can remove the fill caps on a flooded battery you can measure the voltage of each cell. There are losses when charging any battery that you may not be considering. At two amps it may eventually get there but not in twenty hours.
Now when charging the battery at an idle it will take many many hours to fully charge a lead acid battery. Surface charge fairly fast but fully saturated is much longer.
That is part of the beauty of Lithium and other advanced chemistry, density and speed.

Sat Dec 02, 2017 2:45 pm

I would be Interesses in your Setup. Any possibility to Share Pics and Wiring Diagramm? BOM?

I will make a presentable diagram and then share it along with some pictures. All I have at the moment are notes and scribbles.

Dan

Sat Dec 02, 2017 3:45 pm

My understanding is that you can get your battery up to 95% pretty fast it's the last 5% that takes lot's of time. (Also a limiting factor would be your cable from the alternator.) So for a 100 battery 1/2 empty you need 50, with a alternator figure on two hours or so to get it to 95% then it might be many hours to get the final 5%. So get it up then use your solar for final top up. As far as setup with solar it's pretty easy. Solar panel to charge controller to battery. Figure total max amps for solar panel production for wire size. Place controller as close to battery as possible. Go one step up between controller to battery for wire size.

Sat Dec 02, 2017 5:22 pm

Consumption of 4 lights on High beams, any accessory LEDs on, high speed fan running, engine running energy usage, the stereo with any amps and/or sub on, heaters running along with a fancy fridge chilling your microbrews and what not, winch on full load AND charging the batteries are what needs to be allowed for.

Sat Dec 02, 2017 5:42 pm

syncrodoka wrote: Consumption of 4 lights on High beams, any accessory LEDs on, high speed fan running, engine running energy usage, the stereo with any amps and/or sub on, heaters running along with a fancy fridge chilling your microbrews and what not, winch on full load AND charging the batteries at 14.4V are what needs to be allowed for.
Fixed that for you. ;)