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alternator problem RE!!

  • Thread starter Thread starter neikoblu
  • Start date Start date May 9, 2005

neikoblu

New Member
May 9, 2005
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0
Barksdale AFB, Lousyanna
May 9, 2005
#1
  • May 9, 2005
  • #1
I have a 90 mustang. I built a 331 stroker and dropped it in but I seem to have a charging problem. It actually has been there since I bought the car. So I decided to upgrade to a one wire 200amp 3G alternator. The only problem that I have is that I have underdrive pulleys and the company told me that high output alternators don't work well with underdrive pulleys. Does anyone know what I could do before I sacrafice my underdrive pulleys?
 
D

Daggar

New Member
Jul 19, 2004
3,902
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0
May 9, 2005
#2
  • May 9, 2005
  • #2
Sure... purchase an overdrive pulley from March or find a smaler pulley from a different alternator. I think that PA-performance also might have this pulley if you can't find something locally. If you still have your stock alternator, check it's pulley size. If it's smaller than the one on your 3G then give it a try.
 

Stang8URMPRT

Active Member
Dec 28, 2003
1,100
1
38
Daytona Beach, FL
May 9, 2005
#3
  • May 9, 2005
  • #3
I bought my overdrive alt pulley from Summit. ASP pulley. Works like a charm. Keeps full volts at my idle (600-650ish) with my underdrive crank and water pump pulleys.
 

HISSIN50

"How long does it take to get help in here?
15 Year Member
Nov 29, 1999
31,179
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129
May 9, 2005
#4
  • May 9, 2005
  • #4
if warranty is a concern, check with the manufacturer/vendor of the alt first. many wont honor warranty claims if the alt was overdriven.

good luck.
 
D

Daggar

New Member
Jul 19, 2004
3,902
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0
May 9, 2005
#5
  • May 9, 2005
  • #5
HISSIN50 said:
if warranty is a concern, check with the manufacturer/vendor of the alt first. many wont honor warranty claims if the alt was overdriven.

good luck.
Click to expand...


In effect though... you're not really overdriving it. Just compensating for the underdrive pullies.
 

HISSIN50

"How long does it take to get help in here?
15 Year Member
Nov 29, 1999
31,179
33
129
May 9, 2005
#6
  • May 9, 2005
  • #6
Daggar said:
In effect though... you're not really overdriving it. Just compensating for the underdrive pullies.
Click to expand...
yeah, Dags, I totally get that. you are getting the alt back to its engineered idle and critical speeds. but the manufacturers often dont really care about that and wont honor the warranty. i just toss that out as something to remember if a warranty issue comes about.
 

Stang8URMPRT

Active Member
Dec 28, 2003
1,100
1
38
Daytona Beach, FL
May 9, 2005
#7
  • May 9, 2005
  • #7
Yep. I emailed Alterstart about installing an overdrive pulley and he said it's fine, and he has no problems with it and it's still covered under full warranty. I have the e-mail saved to prove it. LOL.
 

neikoblu

New Member
May 9, 2005
63
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0
Barksdale AFB, Lousyanna
May 10, 2005
#8
  • May 10, 2005
  • #8
I never really tried forums before but man this is great. I never realized that I would get so much feedback. You guys are great! I will be helping anyone that I can with the knowledge that I have.
 

HISSIN50

"How long does it take to get help in here?
15 Year Member
Nov 29, 1999
31,179
33
129
May 10, 2005
#9
  • May 10, 2005
  • #9
neikoblu said:
I never really tried forums before but man this is great. I never realized that I would get so much feedback. You guys are great! I will be helping anyone that I can with the knowledge that I have.
Click to expand...
i hear ya. Soon you will be a SN junkie like the rest of us.

nothing like collective knowledge and experience.
 
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