High Output Alternator for LR3

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Needing to replace the 200k mile now-howling alternator on the 2008 LR3 v8. Looking at options for higher output than the stock model. Will be adding more and more electronics, charging stations, lights, *****, etc over time and feel like the stock alt and battery setup barely takes care of the factory load. Dual battery setup coming soon and Thinking an overland trailer will likely happen next year. Will likely have solar assistance on the trailer but want to make sure I’m planning ahead so the truck has some power available to send back there if needed.

Any experience with this upgrade? Recommendations?

Looking at this one, but not sold just yet. https://www.powerbastards.com/products.asp?cat=146372&navsid1=1445&navsid2=146371
 

BendRover123

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I installed one from quality power:

Item #: 11206-240A

So far so good, you do have to swap the pulley from the OEM original with the one they give you with the quality power alternator that won't fit.


Needing to replace the 200k mile now-howling alternator on the 2008 LR3 v8. Looking at options for higher output than the stock model. Will be adding more and more electronics, charging stations, lights, *****, etc over time and feel like the stock alt and battery setup barely takes care of the factory load. Dual battery setup coming soon and Thinking an overland trailer will likely happen next year. Will likely have solar assistance on the trailer but want to make sure I’m planning ahead so the truck has some power available to send back there if needed.

Any experience with this upgrade? Recommendations?

Looking at this one, but not sold just yet. https://www.powerbastards.com/products.asp?cat=146372&navsid1=1445&navsid2=146371
 
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You just got 200,000 miles out of the OEM alternator. Let that sink in...

yes, I’m sold out on these rovers. If you take care of them and do preventative and preemptive service and repairs, the quality of the build really starts to show. I’m grateful to drive vehicles that have character, personality, and even The eccentric quirkinesses Our rovers have! And to really get to know the incredible design and thought that went into these beasts. I’m rarely one to replace OEM with aftermarket alternatives without a ton of research and understanding. There’s a reason LR does EVERYTHING they do.
 
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So to update everyone, yesterday I received my new alternator from Power Bastards, and installed it last night. The process went seamlessly well and the new part was a perfect fit. Drove it last night to test it, and ran errands today and it’s doing great so far. Similar to when you replace a battery in these LR3’s, and everything works better with the new battery, I found the same with the new alternator.

I was hoping my TPMS signal issue was going to magically go away, but as of yet it’s still there... guess I need to look into that more now.

I’ll update in a week or so to let y’all know how the Alternator is doing.
 

gsxr

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Keep in mind that alternators have TWO ratings. One is peak output at a specified RPM. The other is the output at idle RPM. This will vary somewhat depending on the pulley size. Often, "high output" alternators sacrifice idle output, in exchange for peak output.

If you need more current while driving down the road, or while holding the engine up at ~2000 RPM, fine. But if you want the higher current at idle, the "high output" unit might actually be worse.

In the photo below of a Bosch 150A, the rating shown means 90A at idle, 150A peak. Adjusted for pulley size this very roughly translates into peak output around 2000rpm or so. Spinning the alternator faster than peak rated output does nothing.

EDIT: I see the 250A unit you link to claims to have excellent idle output, which is great. Now you need to decide if you really need that much....

upload_2020-9-21_7-54-22.png
 

BendRover123

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Ditto that I killed my Odyssey $250 AGM 950CCM battery in less than a year I believe was partially the fault of the high output alternator I installed from Quality Power.

The stock alternator on idle generates 14V (Denso) you need the voltage to drive battery charging. On idle 500-1000 the Quality Power High Amp alternator I installed (250AMP) drops to 13.1 Volt and that would take forever to charge any large battery with (for that you rather want say 14.5 Volts for some healthy charging). Everything above 12.9 Volt will charge a battery but it will take forever and when your in a hot climate or say on a hot day with the engine running the voltage needs are even higher for das acids batteries.

So what you have to discuss is not only Amps but also Voltage! So I changed my battery to a regular flooded one which take last about ~0.5 Volt lower charging Voltage than AGM and might be more digestible with my after market alternator. If I **** that battery say in 1-2 Years I'll install the OEM Denso type alternator.

My recommendation is if you don't need the extra AMPs don't install a high output alternator. I installed mine because I have a winch that can draw up to 500AMPs so figured a good alternator would help support the battery and stop it from completely draining.

Keep in mind that alternators have TWO ratings. One is peak output at a specified RPM. The other is the output at idle RPM. This will vary somewhat depending on the pulley size. Often, "high output" alternators sacrifice idle output, in exchange for peak output.

If you need more current while driving down the road, or while holding the engine up at ~2000 RPM, fine. But if you want the higher current at idle, the "high output" unit might actually be worse.

In the photo below of a Bosch 150A, the rating shown means 90A at idle, 150A peak. Adjusted for pulley size this very roughly translates into peak output around 2000rpm or so. Spinning the alternator faster than peak rated output does nothing.

EDIT: I see the 250A unit you link to claims to have excellent idle output, which is great. Now you need to decide if you really need that much....

View attachment 11625
 
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CJZA

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Ditto that I killed my Odyssey $250 AGM 950CCM battery in less than a year I believe was partially the fault of the high output alternator I installed from Quality Power.

The stock alternator on idle generates 14V (Denso) you need the voltage to drive battery charging. On idle 500-1000 the Quality Power High Amp alternator I installed (250AMP) drops to 13.1 Volt and that would take forever to charge any large battery with (for that you rather want say 14.5 Volts for some healthy charging). Everything above 12.9 Volt will charge a battery but it will take forever and when your in a hot climate or say on a hot day with the engine running the voltage needs are even higher for das acids batteries.

So what you have to discuss is not only Amps but also Voltage! So I changed my battery to a regular flooded one which take last about ~0.5 Volt lower charging Voltage than AGM and might be more digestible with my after market alternator. If I **** that battery say in 1-2 Years I'll install the OEM Denso type alternator.

My recommendation is if you don't need the extra AMPs don't install a high output alternator. I installed mine because I have a winch that can draw up to 500AMPs so figured a good alternator would help support the battery and stop it from completely draining.
I have been scratching my head and doing some research about this topic. My AAA Branded AGM (H8) battery (date coded to 09/2021) died suddenly and spectacularly on Sunday almost leaving us stranded. Luckily I had a NOCO jump starter with me and managed to get it home. Had to clear trouble codes a couple times with the GAP tool because of insufficient voltage that kept putting the car into limp mode - no power and refused to do more than 10mph. AAA won't honor the warrantee on the battery, so I will be buying a new battery.

Since the car is 17 years old with 127K miles, I thought it may be a good idea to just renew the alternator, drive belt and tensioner pulley at the same time. Got some prices for a new OEM Denso alternator (Cheapest I could find was for $250) and looked at the specs (Peak 150A and 90A produced at Idle). Since I want to install a winch, DC to DC charger and some driving lights and seeing that the LR3 is so sensitive to undervoltage situations, I started looking at high output alternators.

I had a look at and spoke to the following high output alternator companies:
1. Quality Power - Based in CA - 140A idle, 240A Peak - Voltage regulated at 14V - Price $425 - Lead time = 5 days to build.
2. Power Bastards - Based in CA - 125A idle, 250A Peak - Voltage regulated at 14V - Price $425 - Lead time = Same day dispatch.
3. JS Alternators - Family business based in SC - 180A idle, 250A Peak - Voltage Regulated @ 14V/14.8V (you can specify) - Recommends 0.5" Smaller serpentine belt, and big 3 cable upgrade - Price $359 - Lead time = 15 days to build.
4. Tucson Alternators - Family business, based in AZ - 190A idle, 250A Peak - Voltage regulated @ 14.8V - Recommends 0.5" shorter serpentine belt, and big 3 power cable upgrade - Price $379 Lead time = 24 to 48h.

Two of these companies advise on their website - and also did so on the phone - that every high output alternator should be accompanied with a big 3 power cable upgrade. This makes sense, as there is no point in installing an alternator capable of delivering almost double the amperage if the power cables cant cope. The way of doing so is installing the new cables in conjunction with the standard cables (essentially in parallel).

I also read a lot about AGM Batteries and the voltages required to charge them. I even called Full River in California on advise from JS Alternators. For bulk charging, AGM requires 14.3V at 104F and 15.3V at 32F. Float charging requires 13.4V at 104F and 14.3V at 32F. We know that our OEM alternators will not deliver those voltages, so our alternators fail to ever recharge AGM batteries fully, which "significantly shortens their lifespan" (I have read this multiple times).

Questions:
1. If I consider that most of the battery manufacturers give a 3 year warranty on batteries, and my AGM battery lasted 35 months, I can only deduce that AGM expected lifecycle is roughly 36months. How much more could I expect if the AGM battery is charged exactly right? How does that compare to a Lead Acid?
2. If I were to install an alternator with a 14.8V regulator, I wont ever see 14.8V because the alternator output voltage is controlled by the vehicles ECU. So I can never fully charge an AGM battery?

Conclusion:
There is no benefit to installing a high output alternator in combination with a flooded lead acid battery, as the battery wont accept a charge at the same rate as an AGM.
AGM is better for winching/DC to DC charging applications because it is more likely to recover quickly from the demand placed on it and can be discharged more than Lead Acid (80% vs 50%).
A high output alternator should help to eliminate load based voltage drops, but alternator output Voltage is still controlled by the ECU.
Land Rover LR3 ECU alternator control seems to be set to Lead Acid chemistry judging by the voltages we see.
We can prolong the life of AGM by topping it up with an external charger every two weeks to one month, but the charging system in the LR3 will never fully charge AGM.

Would love to have your feedback!
 

itsaguything

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Do you really want it ;-)

Truly, as a flooded battery has a different charging requirement from anAGM battery. And as the generator/rectifier solution in a LR3 is geared towards a flooded battery, I would not be spec'ing an agm.
Also, the warranties. Who cares. The pro-rated warranties give you back pennies on the dollar. They are there to entice you to keep coming back for the their sub quality product.
So, consider a different approach. Either OEM (a high quality solution). Or go BIG and get an optima solution.

Cheers
 

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