Upgrading Alternator will Save Money? Now With Curve Charts!

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Jwithing

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I'm thinking about picking up one of these bad boys 320a powder coated black.

Should give me at least 5mpg, right? :D

My 2 10JLW6V3s like to make my headlights dim after the ATI UD pulley. I'll even get an evic message every now and then if I'm stuck at a red light too long.
 
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Mister Luck

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I'm thinking about picking up one of these bad boys 320a powder coated black.

Should give me at least 5mpg, right? :D

My 2 10JLW6V3s like to make my headlights dim after the ATI UD pulley. I'll even get an evic message every now and then if I'm stuck at a red light too long.
I don’t know about the company have you read any reviews?
Gale Banks likes MechMan alternators probably because he gets them for free but do pay for return shipping for warranty work
I think the warranty on MechMen Alternators are a little longer too but that’s relative to the initial costs.
Does JS have a billet option?


About 20 years ago there was a flood of Asian remanufactured Alternators and some rebuilders were buying them at $5.00 apiece it didn’t matter if they were properly tested because if you sold one for $50.00 you still had 10 chances to keep a profit.

I like to know what’s inside and local rebuilders can pretty much match or surpass or anything out there if you find one that actually tears your original down cleans it and rewinds it , they can rebuild it better than new. Saving $200.00 on a replacement is like 2 free tanks of gas to me.

When having to rely on alternative energy sources one selling point is made of whether or not it is safe for our sensitive electronics. If the energy we use is under preforming then the costs spill over into extra maintenance and replacement of those components and their systems.
 

Jwithing

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I don’t know about the company have you read any reviews?
Gale Banks likes MechMan alternators probably because he gets them for free but do pay for return shipping for warranty work
I think the warranty on MechMen Alternators are a little longer too but that’s relative to the initial costs.
Does JS have a billet option?


About 20 years ago there was a flood of Asian remanufactured Alternators and some rebuilders were buying them at $5.00 apiece it didn’t matter if they were properly tested because if you sold one for $50.00 you still had 10 chances to keep a profit.

I like to know what’s inside and local rebuilders can pretty much match or surpass or anything out there if you find one that actually tears your original down cleans it and rewinds it , they can rebuild it better than new. Saving $200.00 on a replacement is like 2 free tanks of gas to me.

When having to rely on alternative energy sources one selling point is made of whether or not it is safe for our sensitive electronics. If the energy we use is under preforming then the costs spill over into extra maintenance and replacement of those components and their systems.
I don't know about all them words, but the red one sure is purdy. :gr_grin:

In all honesty, I was just putting together a parts list for a 6.4 longblock build so that I can get a better idea of costs. I figured i'd finally upgrade when I pull that trigger. The JS alternators were one of the first HD ones to pop up and I'll definitely do a bit more research before pulling the trigger.

I don't see a billet option for the Mechman, is it billet internals or just casing? Don't really need billet casing. I pass every year on the billet black friday sale lol. It's kind-of nice that JS alternators tells you exactly thay you'll need a half inch shorter belt. I'll need 71" since I have the UD pulley. Mechman pretty much tells you that you need a shorter one and figure it out lol. Mechman also only has a 370 amp for Rams. I need to double check, but I think 320 amp is plenty for me. I'll just want to check output at idle speeds and see if I want to pay more for the extra juice there.

I made my 1/0 big3 cables 3 years ago. I went to price new cables since mine are dingy. Went from $56 to $138. I guess I'll be degreasing mine lol.
 
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Mister Luck

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I think if you just use 6 awg as dedicated ground and positive leaving the factory wire harness you’d have something equal or close to 3 awg

What diameter is your alternator pulley
I have a 55mm on my 160A

Whats your positive battery fuse rated ?
 
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Jwithing

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I think if you just use 6 awg as dedicated ground and positive leaving the factory wire harness you’d have something equal or close to 3 awg

What diameter is your alternator pulley
I have a 55mm on my 160A

Whats your positive battery fuse rated ?
I'll just degrease what I have and stick with the 1/0 awg. I probably have the same alternator if that's stock, not sure what they came with. Fuse is 125.
 
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Mister Luck

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I'll just degrease what I have and stick with the 1/0 awg. I probably have the same alternator if that's stock, not sure what they came with. Fuse is 125.
The fuse to your positive battery post attached at the lug has a separate rating it usually is what your stock alternator is rated which in my case is 160A .
(EDIT double checked my fuse is 180A)

If I want to upgrade my alternator
I’m going to upgrade my fuse
The highest rating I can find for the OE part is 220A.


63F55ECD-D336-433B-9792-F88994D1CBDB.jpeg
 
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Jwithing

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The fuse to your positive battery post attached at the lug has a separate rating it usually is what your stock alternator is rated which in my case is 160A .
(EDIT double checked my fuse is 180A)

If I want to upgrade my alternator
I’m going to upgrade my fuse
The highest rating I can find for the OE part is 220A.


View attachment 484225
Oh I misunderstood what you were asking. Thought you were asking about my inline fuse for my sound system. That's 125a. Post fuse is whatever stock is, so I assume 180 as well.
 
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Mister Luck

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Oh I misunderstood what you were asking. Thought you were asking about my inline fuse for my sound system. That's 125a. Post fuse is whatever stock is, so I assume 180 as well.
Do you have any suggestions for an inline fuse thats 320A for the positive battery cable since you seem to know something about them.
 

Wild one

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Do you have any suggestions for an inline fuse thats 320A for the positive battery cable since you seem to know something about them.
You'll burn the truck up,using a 320amp fuse.You put 320 amps into the stock wiring,there's gonna be a hell'va smoke show in a very short order.Stick with the stock fuse,or at most the higher amp 220 factory fuse.If you haven't noticed,all the higher amp alternators reconmend upgrading the wiring,so get off your ass and do the Big 3 as it's called,which i've been telling you to do for a week or more now,lol. And don't use 6 gauge,at least use 4 gauge even if you're piggy backing the factory wiring.There's a stud behind the battery,that makes for a good junction block to run your extra grounds from,i'd run extra grounds to both the fender grounds,from the engine to the ground stud,and from the frame to the ground stud,also doesn't hurt to run an extra ground from the back of the frame to the box,if you're really ambitious you can even run a ground to the pass side frame rail,that way both sides of the frame are grounded solidly.I even ran a ground to one of the studs that the PCM mounts to
 
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Mister Luck

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I can only find 300A automotive fuses but holder is rated for up to 500A this is for someone who wants to do the big three using a larger that stock alternator
( 220A)
 
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Wild one

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I can only find 300A automotive fuses but holder is rated for up to 500A this is for someone who wants to do the big tbree using a larger that stock alternator ( 220A)
Doesn't matter,the interior wiring/headlight wiring ,fuse box etc.,won't handle 320 amps,you must think the wiring ends at the engine or something,lol.Stick with the factory 220 fuse at most.Go back and reread my post,i just updated it.
 

Wild one

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Maybe you should go back and read all the post over then you’d be on the same page.
You must be a little bit dense,how do you think i picked up on the aftermarket alternators all reconmending upgrading the wiring,lol. You sir,make me shake my head,as you seem to be a bit stubborn to accept any advice from the guys who've done the wiring upgrade,several years ago,no less,lol.Tough to accept somebody else might know as much or more then you,lol
 
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Mister Luck

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Alternator selection formula

(RATIO)

(In mathematics, a ratio indicates how many times one number contains another)

5.7 HEMI Crank Pulley Diameter

6.249 inches

Divided by

Alt Pulley Diameter

2.1654”

= 2.88

Engine RPM X RATIO = Alternator RPM

RATIO = 2.88 (X Engine 600 RPM) = 1,728

( alternator RPM ) 1,728 / 1800 = 1.04

minimum of 1800 RPM to generate output
 
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Wild one

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Its like your keystokes are coming in at 100 mph and your mind is going 2 mph
Why are you aggravated only on the weekends?
I'm over here laughing at you,but you can think whatever you want,if it makes you sleep better,:gr_grin::happy160:.Why are you so hung up on not trying out the wiring upgrade,before spending a bunch of money on an aftermarket alternator. That to utilize properly,you need to upgrade the wiring anyways.You seem to have a burr under your saddle on taking advice from the guys that have already did the wiring upgrade.:doh2:
 
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Wild one

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At this point the only problem I have is responding to your nonsense I think it maybe for the better that I ignore your posts when you choose to be disruptive.
Might be the best idea you've ever had,:Big Laugh:. You appear a bit hard headed when it comes to taking advice,:banghead:
 

62Blazer

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Doesn't matter,the interior wiring/headlight wiring ,fuse box etc.,won't handle 320 amps,you must think the wiring ends at the engine or something,lol.Stick with the factory 220 fuse at most.Go back and reread my post,i just updated it.
While I'm trying to stay out of the romper room bickering, I just couldn't resist making some comments. Regardless of what size alternator you install it does NOT require you to upgrade all of the wiring on the truck. Just because the alternator is capable of producing 320 amps doesn't mean it's sending 320 amps through the entire electrical harness of the truck. The amperage flowing through the wiring will only be how much that circuit requires. If the circuit only needs 2 amps than it will only pull 2 amps regardless of the alternator size and rating. The constant is the voltage, which will always be in the 12-14 volt range and the amperage will vary based on how much is needed by that circuit. You increase the wire size in each circuit based on the power demands, and that's why items like the starter and battery leads are big cables.
 
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Mister Luck

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