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Need smaller alternator pulley

4499 Views 24 Replies 11 Participants Last post by  Marcos
Who offers them? anyone on here sell them?
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I got them. smallest available, 52 mm o.d.A socket hardly fits.$24 shipped.
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Those help a little with idle output right?
If you mean alternator output at idle, then yes. The smaller pulley will give you more output.
1-3/4" is the smallest I have seen.
yup, i am running one of ron's pulleys. it picked my voltage up from 10 to 12 at idle
yup, i am running one of ron's pulleys. it picked my voltage up from 10 to 12 at idle
Yup thats all I needed to know, thanks everyone...
I need to do this to mine....eventually.
So you guys add them to your 105 amp alternators? Does the stock belt still fit good with this smaller pulley? Im holding off on a bigger alt. because with an efan running and my 900 watt stereo system running, it needs some more power at idle.
I'm sure they work well, but I'd also think they'd...

a) increase belt wear, due to tighter radius, and...
b) shorten alternator life, due to the greater constant and ultimate RPM
So you guys add them to your 105 amp alternators? Does the stock belt still fit good with this smaller pulley? Im holding off on a bigger alt. because with an efan running and my 900 watt stereo system running, it needs some more power at idle.


You just need to purchase a 145A and the OD alt pulley.
I'm sure they work well, but I'd also think they'd...

a) increase belt wear, due to tighter radius, and...
b) shorten alternator life, due to the greater constant and ultimate RPM
true it would seem that way, but ive had mine like this for about 1.5 yrs on a 145A, no problems, if the alt craps out i still have my stock 105 to get around on for a while, and i will just order a higher amp alt, its worth it to not see my volts drop to 12.8 while idling and the e-fans come on, now they only drop to about 13.5 and then go right back up to 14
Fair enough...I can see it being a less expensive option to replacing a functioning alt. I'd just keep an eye on the belt, checking for accelerated wear.
Fair enough...I can see it being a less expensive option to replacing a functioning alt. I'd just keep an eye on the belt, checking for accelerated wear.


$40-70 isn't much and you pick up FOURTY amps, that's a vast amount.
Well I like the way this thing is working, when my e-fans kick on it doesn't drop to 10
is it a bitch to get the pully off? can it be done while the alt is in place?
I do think so.
is it a bitch to get the pully off? can it be done while the alt is in place?
yep:shake: i removed the belt, grabbed ahold of the stock pulley and hit the nut on it with an impact wrench. backed it right off. had the old one off and the new one on within two minutes.:jester:
I would leave the belt on and hit it with the impact. Worked fine for me.
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