High ouput alternator and serpentine belt

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youredoingitpeter

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I've been seeing posts about members installing high output mechman or JS alternators and some I've seen have installed different size serpentine belts. But I haven't found anyone saying what size, part number, or interchange number.
Is it necessary to have a different size than stock belt for an ** alternator?
I have a 2019 tahoe 5.3L.
I just installed a 240a alternator (local shop built) and a big 3 setup this weekend. Im planning on changing the belts and tensioner, but I dont want to buy an oem serpentine belt if it's not going to benefit my upgrade.
TIA
 

Marky Dissod

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I've been seeing posts about members installing high output mechman or JS alternators and some I've seen have installed different size serpentine belts.
But I haven't found anyone saying what size, part number, or interchange number.
Is it necessary to have a different size than stock belt for an ** alternator?
I have a 2019 tahoe 5.3L. I just installed a 240a alternator (local shop built) and a big 3 setup this weekend.
Im planning on changing the belts and tensioner, but I dont want to buy an oem serpentine belt if it's not going to benefit my upgrade.
2 questions:
1. What is 'an ** alternator'?
2. Is this this forum's bad word police again? 2a: there's a bad word with only two letters? Seriously? Need to learn this word!

Nothing to do with high output alternators: whenever possible, I buy a Gates serpentine belt that is up to one inch shorter than GM OE.
 
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youredoingitpeter

youredoingitpeter

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2 questions:
1. What is 'an ** alternator'?
2. Is this this forum's bad word police again? 2a: there's a bad word with only two letters? Seriously? Need to learn this word!

Nothing to do with high output alternators: whenever possible, I buy a Gates serpentine belt that is up to one inch shorter than GM OE.
First letters.... High Output. Thats the **.
Do you have a part number for that belt? Thanks
 

Marky Dissod

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1st: getting sick of this forum's bad word judge. Is there any redress?
2nd: measure the belt in inches, then look at the last few digits of the part number.
You want to change the part number to represent a belt that is (up to but no more than) one inch shorter.
 

Marky Dissod

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LOL, so '**' means 'working girl from the 'hood'? Good Lord.
Whose 3rd grader did they hire to be the censor here?
And why have we zero ability to lobby for common sense adjustments to this puerile 'policy'?
 

homesick

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And why have we zero ability to lobby for common sense adjustments to this puerile 'policy'?

Maybe our 3rd grader has his/her fingers in his/her ears, going "LA LA LA LA LA".

joe
 

k_arnold72

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I installed a h.o. alternator but reused the exact same belt. But when I compared them side by side, the old and new units has the same diameter pulleys.

Any pics of the big 3 upgrade? I've been thinking about doing that, so I'm wondering what mounting points you used?

I've been seeing posts about members installing high output mechman or JS alternators and some I've seen have installed different size serpentine belts. But I haven't found anyone saying what size, part number, or interchange number.
Is it necessary to have a different size than stock belt for an ** alternator?
I have a 2019 tahoe 5.3L.
I just installed a 240a alternator (local shop built) and a big 3 setup this weekend. Im planning on changing the belts and tensioner, but I dont want to buy an oem serpentine belt if it's not going to benefit my upgrade.
TIA
 
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OP
youredoingitpeter

youredoingitpeter

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I installed a h.o. alternator but reused the exact same belt. But when I compared them side by side, the old and new units has the same diameter pulleys.

Any pics of the big 3 upgrade? I've been thinking about doing that, so I'm wondering what mounting points you used?
Ill get some pics later on for you
 

Dirty looks

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I installed a 350 amp H.O. that had a smaller pulley. Required a one inch shorter belt. Napa parts man figured it out.
I like the smaller pulley for better proformance at idle and improved cooling. Set up for overlanding my power requirements are ridiculously high.
Keep your cables clean.
 

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