Upgrading Alternator will Save Money? Now With Curve Charts!

Wild one

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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.
Show me a one way clutch pulley for the stock Ram 4th Gen alternator?
If i'm reading his post right,he's looking for something to freewheel the alternator under low use situations,which would entail something with an electrical magnetic clutch,or some way to decouple the pulley from the alternators armature shaft,not a 1 way clutch
 
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kurek

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Show me a one way clutch pulley for the stock Ram 4th Gen alternator?
If i'm reading his post right,he's looking for something to freewheel the alternator under low use situations,which would entail something with an electrical magnetic clutch,or some way to decouple the pulley from the alternators armature shaft,not a 1 way clutch

I have no idea what OP wants, I don't think OP has any idea what he wants. He read some thing is cool and now he absolutely definitely wants that thing despite that it won't actually provide him any benefit.

I never said there was an alternator clutch pulley for our trucks, I said
I've never seen a clutch/damper/overrun pulley conversion kit . I've seen kits for going the other way (clutch to solid).

 

Randy Grant

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I really don't think that the measurable gain , if you could measure it, would ever be enough to pay for the larger alternator.
 
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Mister Luck

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The clutch pulley has been around since 1997 the decoupler pulley is more recent and more specialized in its most recent incarnation in that it is tuned to the number of cylinders.

A clutch pulley is just a one way drive they are owned by no particular engine but mainly used to reduce parasitic drag and stress on the tensioner pulley and an engines belt drive.

I wouldn’t want anyone to be misguided into thinking there’s a secret application where “tuned”decoupler pulley’s exist for cylinder displacement engines , I actual only discovered Decouplers 2 days ago.

Today I took the time to look at the back of my alternator to see what
I thought had been (in my mind) a 180A
alternator with a 2.7 in (solid) pulley
It turns out my truck has a 160A alternator with a 55mm pulley in other words a 2.16 inch diameter pulley , this is something the specifications don’t cover and probably something borrowed from the other family members of FCA Stellantis. Jeep Dodge Chrysler production that is also assembled in Mexico.?
 
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Mister Luck

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The messed up design of the decoupler pulley is the relative cost I’m pricing some of these pulleys alone mind you at $200.+ low end are $80.+ and some manufacturers don’t sell replacements , they want you to buy and replace it with another alternator, there is a specialized tool for those who offer aftermarket replacements but warn the consumers not to interchange pulley designs or warranties will be voided.
An overdrive pulley is what brought on this discovery of pulley design that I am thankful my truck doesn’t possess.
I think it has to be much more economical to replace idler pulley, tensioner pulley and aux pulley bearings than what is cost for a clutch or decoupler style pulley.
 

Wild one

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The messed up design of the decoupler pulley is the relative cost I’m pricing some of these pulleys alone mind you at $200.+ low end are $80.+ and some manufacturers don’t sell replacements , they want you to buy and replace it with another alternator, there is a specialized tool for those who offer aftermarket replacements but warn the consumers not to interchange pulley designs or warranties will be voided.
An overdrive pulley is what brought on this discovery of pulley design that I am thankful my truck doesn’t possess.
I think it has to be much more economical to replace idler pulley, tensioner pulley and aux pulley bearings than what is cost for a clutch or decoupler style pulle
 
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Mister Luck

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EDIT
Yeah those are vehicle specific Decouplers
OAD if we were to adapt one for our trucks it would be OAP

 
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Mister Luck

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Rebuilding an alternator might be a better option


This also could be considered preventative maintenance which could save you money considering the price of a new or rebuild alternator .
 
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Mister Luck

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I believe the reason this and other automotive forums are valuable is because of the exchange of information
If all that is gone with members reluctant or harassed when asking legitimate or answering legitimate questions then we are failing as a community.
For the most part the majority of the members have an understanding of this and are great examples known by their contributions.
 
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