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Low idle alternator

  • Thread starter Thread starter RoryM
  • Start date Start date Jul 28, 2005
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RoryM

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May 26, 2005
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#1
  • Jul 28, 2005
  • #1
What company carries alternators that charge with a low idle rpm? I have a race only pulley with a medium sized stereo with the stock rebuilt alternator. At this time I have to be at 2500rpm to charge the battery and its a exspensive Optima. If no one knows of a low idle alternator im going back to the street pulley.
 

HISSIN50

"How long does it take to get help in here?
15 Year Member
Nov 29, 1999
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Jul 28, 2005
#2
  • Jul 28, 2005
  • #2
Alts from places like PA and Alterstart will can be had where they charge at low rpms. If that does not cut it, overdriving the thing works for many folks.


Good luck.
 

grey5.0beast

Cookies should never be DUNKED!!!
Aug 3, 2004
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atl ga
Jul 28, 2005
#3
  • Jul 28, 2005
  • #3
many people ditch the alternator pulley and just run he other underdrives. this problem is very common and u will not lose much hp from using the stock pulley for the alt
 
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rflow50

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#4
  • Jul 28, 2005
  • #4
What year is your car and if you have an expensive optima, why not have a 130amp alternator for it. The alternator on 87-93 mustangs have 75amps, and with any extra stuff you put in your car they suck. do the conversion, if that's your case and change it to a higher amp alternator.
 
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RoryM

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May 26, 2005
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#5
  • Jul 28, 2005
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Its a 91 notchback that will see some traffic driving once and awhile. Im looking at a powermaster that gives 140 amps, but I wanted to know if anyone knew of "low idle charging" alts since I dont charge unless im at 2500rpm.
 

QDRHRSE

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Dec 31, 2002
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Jul 28, 2005
#6
  • Jul 28, 2005
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You could use the alternator out of a sn95 mustang or you could get a 3G.
 

sgarlic

Founding Member
Apr 21, 2001
3,085
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Jul 28, 2005
#7
  • Jul 28, 2005
  • #7
I would go with the 3G upgrade. Refer to fordmuscle.com for the basics, but you can find a junkyard 3g alternator for 40-50 bucks, then buy the power wire and fusible link from autozone, or PA Performance if you want the entire kit. It's pretty simple, and will more than likely cure all your charging problems.
 

HISSIN50

"How long does it take to get help in here?
15 Year Member
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Jul 28, 2005
#8
  • Jul 28, 2005
  • #8
Or if you are not liking the options out there (FWIW, i just installed a Boss 170 amp alt - 75 amps at 'idle'), you can talk to a local shop and have them wind the alt however you want (I think they can reverse wind one too - so you have good output at idle but less parasitic loss at higher revs. Good for racing).

Rory, do you even have a self-exciting alt right now?

Good luck.
 
8

8950HO

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Mar 31, 2005
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#9
  • Jul 28, 2005
  • #9
RoryM said:
What company carries alternators that charge with a low idle rpm? I have a race only pulley with a medium sized stereo with the stock rebuilt alternator. At this time I have to be at 2500rpm to charge the battery and its a exspensive Optima. If no one knows of a low idle alternator im going back to the street pulley.
Click to expand...

Get rid of the "race only pulley" for the street,and use a street size underdrive crank pulley instead.
You can always install a smaller overdrive alternator pulley 1-7/8" from www.aspracing.com for better low speed charging.

a 130amp 3g alternator from a 94-95 mustang is a good upgrade,although higher amp alternators are available for more $$$.

www.pa-performance.com has high output at low speed alternators
 
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RoryM

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#10
  • Jul 28, 2005
  • #10
The 3G was just ordered...Thanks guys
 
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