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I have a 3.0 with a 220A stock alternator. Would love a 370A alternator to feed an aux Yellow Top I installed to help feed my 5 amplifiers.
BUT, the stock unit has worked pretty well for just over a year now with that drain. Post pics and specs when you upgrade please.

Can you post pics of the battery isolator you used and details of the setup? I'd like to add a battery and amplifiers, etc. to my rig.
 

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if you don't need a bigger alternator, but needed to replace your would their be any benefits upgrading to a bigger mopar alternator? better battey charging? or not worth it at all?
 

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if you don't need a bigger alternator, but needed to replace your would their be any benefits upgrading to a bigger mopar alternator? better battey charging? or not worth it at all?
Couple ways to look at it...

If you've never had problems keeping up with electrical loads with the alternator you have then there is no value in getting a bigger one. If the most you need is 110 amps, you'll get 110 amps from a 180 amp alternator and you'll get 110 amps from a 220 amp alternator. The bigger alternator gives no benefit.
 

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Couple ways to look at it...

If you've never had problems keeping up with electrical loads with the alternator you have then there is no value in getting a bigger one. If the most you need is 110 amps, you'll get 110 amps from a 180 amp alternator and you'll get 110 amps from a 220 amp alternator. The bigger alternator gives no benefit.
I bigger alternator would potentially provide the 110a at lower engine speeds (idle for instance), where the alternator fan cannot cool as well.
 

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.....I'd be wary of installing an aftermarket alternator on a V6; the EHPS is chewing up the factory alternators and I'm not sure an aftermarket will put up with that punishment..
What is the EHPS? and what is it doing to the alternators to chew them up?

[EDIT] Electro-Hydraulic Power Steering? The V8's don't have it, and in my case and other posts on the forum, it seems the V8's suffer early failing Alternators as much as the V6's... ...several Aussies are posting about it, rather livid they fail so soon....
 

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I know this is an older post, but has anyone installed a mechman high output alternator with the smaller pully? Trying to find out what size belt to get and where to get it.
Most belt manufacturer's the length of the belt is in the part number, if not, there is surely a guide on their website about the length of their belts to help you choose.
You could do some very simple geometry to determine the difference in length.

But personally, I would mess with a smaller pulley on an alternator. Why do you need that much more ouput? The WK2 alternators aren't falling short in current supply, they simply fail more often than they should. Spinning the alternator faster, I don't see how you're solving anything.

Unless you are doing something unusual that requires double the electric power, getting the highest output OEM should supply more than enough for a WK2 for its typical usage.
 

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Most belt manufacturer's the length of the belt is in the part number, if not, there is surely a guide on their website about the length of their belts to help you choose.
You could do some very simple geometry to determine the difference in length.

But personally, I would mess with a smaller pulley on an alternator. Why do you need that much more ouput? The WK2 alternators aren't falling short in current supply, they simply fail more often than they should. Spinning the alternator faster, I don't see how you're solving anything.

Unless you are doing something unusual that requires double the electric power, getting the highest output OEM should supply more than enough for a WK2 for its typical usage.
Thanks for the reply. I was able to find the Dayco belt sizes on a link Mechman provided in FAQ section of their website.

I didn't need the 370 (at the moment, lol), but the 240 and 320 were out of stock. The stock alternator has held up well, but the 3 audio amps I have in there currently are just a bit too much for 160 amps and my lights dim every now and then. I'm replacing the current amplifiers with more powerful ones and the upgraded alternator is mandatory now. I originally had the base 6 speaker audio with the 8.4 inch Uconect, and while I still have the same 8.4 inch headunit, I've added a PAC BCI module to add 4 cameras and an Amazon Fire stick, PAC Amp Pro, 12 speakers, and 3 amplifiers, and a 10 channel DSP.
 

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This thread reminds me of a guy I used to work with back in the '80s in an auto assembly plant. One of the cars we made was a police vehicle with a high output alternator. The alternator in his truck was failing and he had the bright idea to replace it with one of the high output ones. Instead of buying one he smuggled one out in his lunch box. I heard from someone else months later that he had to have the entire wiring harness replaced in his truck because it burned up due to the overload that it was not designed to handle. A rather expensive lesson.
 

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In the 70's that could likely happen, not sure about the 80's technology but the voltage regulators were usually solid state by then. Perhaps the alternator and voltage regulator wasn't compatible in his truck. Today the voltage regulator/field control is self contained in the alternator itself, but it requires input from the PCM to control the field strength/regulate voltage, so yea, you just grab any alternator and assume it will just work like the one for your vehicle, I can see it causing damage.
 

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Thanks for the reply. I was able to find the Dayco belt sizes on a link Mechman provided in FAQ section of their website.

I didn't need the 370 (at the moment, lol), but the 240 and 320 were out of stock. The stock alternator has held up well, but the 3 audio amps I have in there currently are just a bit too much for 160 amps and my lights dim every now and then. I'm replacing the current amplifiers with more powerful ones and the upgraded alternator is mandatory now. I originally had the base 6 speaker audio with the 8.4 inch Uconect, and while I still have the same 8.4 inch headunit, I've added a PAC BCI module to add 4 cameras and an Amazon Fire stick, PAC Amp Pro, 12 speakers, and 3 amplifiers, and a 10 channel DSP.
Just thinking out loud, I didn't see anything mentioned about a second battery, something you can do for incredibly cheap and a lot less intrusive than replacing an alternator. I learned my lesson with capacitors a long time ago (no matter the size, they still suck), so on my last build I installed a second battery and was able to run for years on a sub 100 amp alternator with zero issues. I was somewhere close to 4650 watts (real watts, not what the amp had stamped on it) and I never had a problem with dimming lights.

When I start my build on my WK2, I have zero plans on upgrading the alternator either.
 

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Just thinking out loud, I didn't see anything mentioned about a second battery, something you can do for incredibly cheap and a lot less intrusive than replacing an alternator. I learned my lesson with capacitors a long time ago (no matter the size, they still suck), so on my last build I installed a second battery and was able to run for years on a sub 100 amp alternator with zero issues. I was somewhere close to 4650 watts (real watts, not what the amp had stamped on it) and I never had a problem with dimming lights.

When I start my build on my WK2, I have zero plans on upgrading the alternator either.
Thought about the second battery, but I have no room for it, plus I don't blast the radio with the engine off. Also, the current draw I require would greatly shorten whatever life is left in the stock alternator because it would need to keep 2 batteries charged. You don't need to see lights dimming to experience voltage drop. And even expensive amps won't last long if they're always starving for power.
 

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Thought about the second battery, but I have no room for it, plus I don't blast the radio with the engine off. Also, the current draw I require would greatly shorten whatever life is left in the stock alternator because it would need to keep 2 batteries charged. You don't need to see lights dimming to experience voltage drop. And even expensive amps won't last long if they're always starving for power.
Just curious, a system that pulls that much current to play music inside a vehicle... doesn't it blow out your eardrums? Or is this one of those competition setups?
 

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anyone still on here? Looking to upgrade my wj overland alt for audio. Wanting 200+ amps is it dangerous to go much higher? Any insight is appreciated I don't know very much about upgrading alternators.
 

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anyone still on here? Looking to upgrade my wj overland alt for audio. Wanting 200+ amps is it dangerous to go much higher? Any insight is appreciated I don't know very much about upgrading alternators.
My WK2 came from the factory with a 220 amp alternator, if that helps.
 
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