Upgrading Alternator will Save Money? Now With Curve Charts!

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Mister Luck

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What you need is info on how much horsepower it takes for each alternator to generate a specific charge current. This topic implies that the 220 a alternator uses less hp to generate 100 A than the 160a alternator.
The Title is proposed in a form of a question (?)
what ever you gain from that is purely conceptual on your part.

Like I mentioned before it depends upon who’s behind the wheel and personal driving habits when you bring fuel economy into question.
 

62Blazer

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What you need is info on how much horsepower it takes for each alternator to generate a specific charge current. This topic implies that the 220 a alternator uses less hp to generate 100 A than the 160a alternator.
Exactly. I'm not convinced that is the case (220 alternator using less HP for 100 A), and even if it was true I would think the difference is so small you wouldn't notice it.
 

indept

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The Title is proposed in a form of a question (?)
what ever you gain from that is purely conceptual on your part.

Like I mentioned before it depends upon who’s behind the wheel and personal driving habits when you bring fuel economy into question.
OK
This Topics title question, :favorites13:, implies that the 220a alternator could use less horsepower to generate 100 a than the 160a one since yes is a possible answer.
Disclaimer: This answer in no way reflects the views of the forum moderators or it's advertisers.

I think I covered all the bases. :D
 

indept

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Exactly. I'm not convinced that is the case (220 alternator using less HP for 100 A), and even if it was true I would think the difference is so small you wouldn't notice it.
They higher output alternators may have lower loss diodes and better windings but as you said the difference is so small that you wouldn't be able to see it. The refilling at the same pump to calculate the mileage would have more repeatability error than the above mpg added.
 
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OK
This Topics title question, :favorites13:, implies that the 220a alternator could use less horsepower to generate 100 a than the 160a one since yes is a possible answer.
Disclaimer: This answer in no way reflects the views of the forum moderators or it's advertisers.

I think I covered all the bases. :D
I think you mean the statement? from rock auto which leaves the question open ended and you’re desperately trying to close .

The title of this thread is not solely based upon the rock auto parts statement it is just an opener. You like everyone else is interested in saving money. .. sorry the thread isn’t providing the answers you hoped for.
 
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What about keeping the same alternator and just changing to an overdrive pulley? Lower engine rpm but faster alternator rpm. Probably fine for low rev diesel but for gas?
 
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What about keeping the same alternator and just changing to an overdrive pulley? Lower engine rpm but faster alternator rpm. Probably fine for low rev diesel but for gas?
I was thinking
a 2.72:1 pulley ,
do you think a 1.91:1 overdrive pulley would be too much ?
 

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This is the first time I have ever heard about this theory of a larger alternator providing better fuel economy. Motorsports has been my hobby for 30+ years and I spent 12 years in the automotive engineering field including a lot of time performing fuel economy testing and sat on SAE (Society of Automotive Engineers who publish recommend test procedures for many things) committees on it. I would have to see the force curves required to turn an alternator at different loads, and see if running an 160 amp alternator at 50% load is really that much higher than a 220 amp alternator at 36% load. I would think that the extra force required to spin the heavier weight internals of the larger alternator would likely counteract any savings you would get but running at a lower load %. This the same basic theory as saying you should put a larger and higher horsepower engine in a car so it will get better fuel mileage.
A larger alternator say double the amps of a current alternator can save fuel. The small one was built to handle just the ratings of the truck and therefore at 50% it will be harder to turn. A larger one would not have to struggle much to give out that 50% of the other one.

 

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#48 is a sales pitch to sell more expensive equipment
Yes components may last longer but but save on mileage is a crock
 
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#48 is a sales pitch to sell more expensive equipment
Yes components may last longer but but save on mileage is a crock
Their explanation is better in the follow up video

“Efficient Alternators Equal Fuel Savings /
BorgWarner Delco Remy”


The percentages are for HD commercial vehicles and the Alternator ends up paying for itself after a couple years or less depending on inflationary fuel costs.
 
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Does the RAM 4TH Generation use an
Alternator Decoupler Pulley ????

 

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#51 is off topic spend the dollars and you can make a more efficient product with less input with same output so again sales pitch
 
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#58 is off topic spend the dollars and you can make a more efficient product with less input with same output so again sales pitch
I think you still meant #48 but yeah it’s about commercial trucks but as most that know about internal combustion engines the theory is relevant,
energy saved is energy gained.
 
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I've never seen a clutch/damper/overrun pulley conversion kit . I've seen kits for going the other way (clutch to solid).

I wish they made retrofits for old alternators I'd put one on my Mustang at least.
 

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Has anyone incorporated a clutch pulley with their alternator?
It's called killing the field wire in the old days,lol.I highly doubt anybody has spent the money to tool up a clutch for a north american built automotive alternator,that'd be huge dollars,and you'd never come close to recouping your money on such a venture.Let us know how you make out at the machine shop having one built
 

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It's called killing the field wire in the old days,lol.I highly doubt anybody has spent the money to tool up a clutch for a north american built automotive alternator,that'd be huge dollars,and you'd never come close to recouping your money on such a venture.Let us know how you make out at the machine shop having one built

They're kinda two different things - nearly all modern cars and trucks are PWM at the alternator and all accessory voltage regulators so they're making a decision to kill the field wire 150,000 times per second.

Alternator clutch pulleys and damper pulleys are a one way clutch, or a one way clutch plus torsion spring that allow the alternator to freewheel if they happen to be going faster than the engine (good to let them spin down on auto start/stop vehicles) and also damp their movement a little similar to a harmonic damper on a crankshaft which supposedly extends the life of the drive belt by reducing constant shock loads on them and extends the life of idler pulley bearings & tensioners, and slightly reduces NVH.

I don't know if any of that can also save energy, probably not enough to add up to the $100+ a hypothetical kit would cost... not in a hundred years of driving. I'm sure the #1 reason so many cars have them now is just for quicker/smoother auto stop/start and any other benefits are just freebies.
 
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