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Alternator Suggestions

  • Thread starter Thread starter 86StangLX
  • Start date Start date Nov 4, 2004
8

86StangLX

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Feb 25, 2004
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#1
  • Nov 4, 2004
  • #1
Hey guys,

After going through quite the fiasco with electric/charging problems I discovered my old alternator was only putting out 34 amps at max peak output. I replaced it with a brand new 80 amp alternator, but it's putting out only 67 amps at max peak output. I'm running underdrive pulleys and a 250w amp powering a 10" sub. So I know where the significant strain on the alternator is coming from. I want to keep the underdrives and I'm definitely not touching my stereo system. So does any know of any direct bolt-in 100+ amp alternators that would work? Thanks.
 
S

Sicarius428

Active Member
Jan 6, 2004
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Nov 4, 2004
#2
  • Nov 4, 2004
  • #2
Don't get a powermaster. I purchased one through summit and the thing doesnt even spin. I called the tech and he instructed me to take it apart to see what it is hanging on which I don't see the point if I payed for one that is supposed to be working. I have heard many people go with the 3G and have been really pleased. You might want to look into those.
Kevin
 

HISSIN50

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Nov 4, 2004
#3
  • Nov 4, 2004
  • #3
86StangLX said:
So does any know of any direct bolt-in 100+ amp alternators that would work? Thanks.
Click to expand...
literally, there is not gonna be such a beast. you will need to do a wiring upgrade for anything rated much higher than stock.

PA offers some nice units (not sure if they drop right in or need clearancing on the mounting bracket like the SN alts do). or a 94-95 alt will work with a little work. there are tons of posts and write ups on most aspects of this upgrade, should you feel like searching.
good luck.
 

TrickStang37

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Oct 17, 2004
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#4
  • Nov 4, 2004
  • #4
alterstart makes some great alternators. 3G 160 AMP alt for 129.99. you will need to upgrade the wiring, which i got through PA performance. there isnt much to installing at all. i run underdrives and with my lights on, electric fan and stereo there is no dimming, but thats also with an ASP overdrive pulley 18.99 through summit. your gonna have to run it with the stereo you have and underdrives.
 
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86StangLX

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#5
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TrickStang37--what is an overdrive pulley? I haven't heard of such a thing. And when you say I would need to upgrade the wiring, how so? Thanks for your help!
 

joelliott

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Nov 4, 2004
#6
  • Nov 4, 2004
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its just the opposite of underdrive pullies. It will turn your alt over faster at all RPMs. Thus increasing the amount of output your alt makes. its good for people with high volt needs like you. Id certainly get one.

I have a question about the wiring upgrade. I see alts on ebay like alterstart 160 amp etc. And they offer wiring systems to hook it up. Is thos the woring upgrade your refering to? Or is ther more? Thanks
Joe E.
 

TrickStang37

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yeah, but im not sure on the quality of it. its probably good, but PA performance sells the kit for like the same price or so and always hear good things from them.
 
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88Trooper

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Nov 4, 2004
#8
  • Nov 4, 2004
  • #8
The SS cars (some, mine at least) had Lesco (Lestek?) 160 amp alternators. There's a guy in VA, I'm sure you guys know him, Jim Dingell with Mustangparts.com has them. They're pricey, like over $400 last time I checked, but mine has lasted over 100k miles, it finally failed a few months ago.
 

cobra dave

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#9
  • Nov 4, 2004
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i just changed my alternator out and i just picked one up at autozone. I'm running underdrives two big amps and 1 12" sub. I do alot of city driving actually thats all i do and i have no problems.
 

jrichker

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Here's websites with pictures of the 3G (94 Mustang and later 130 amp alt) installation procedure...

See http://www.geocities.com/smithmonte/Auto/3G_130A_Alternator_Upgrade.htm - all the tech data you could ever want to know
OR
http://www.mustangcentral.net/tech/alternator.html - excellent pictures of the installation

See these sites for the right way to do the wiring. Some people will tell you that you can skip the wiring upgrade, but it will catch up with you sooner or later. A fire in the wiring harness is ugly and expensive.

Under no circumstances connect the two 10 gauge black/white wires to the 3G alternator. If the fuse blows in the 4 gauge wire, the two 10 gauge wires may be overloaded to the point of catching fire and burning up the wiring harness.

Figure this:
Ignition system & computer = 12 amps
Fuel pump = 12 amps
Exterior lights = 15 amps
Fan (heater or A/C) = 15 amps (can run between 5-25 amps depending on setting)
Radio & instruments = 10 amps
Wipers = 10 amps

That's grand total of 74 amps from a 65 amp alternator. Talk about overdrawn at the bank!

See WWW.partsexpress.com for the fuse & fuse holder.
Fuse = http://www.partsexpress.com/pe/showdetl.cfm?&DID=7&Partnumber=071-952

Fuseholder = http://www.partsexpress.com/pe/showdetl.cfm?&DID=7&Partnumber=263-630
 

NCStang86

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selma,nc
Nov 4, 2004
#11
  • Nov 4, 2004
  • #11
I did the 130amp upgrade on my 86GT and u would beleive the difference it made.My windows have never went up faster than they do now.The actual all around performance is better too.I just got one from a 94-95 and put my underdrive pulley on it and rest is history.Good luck
 

TRWXXA

Member
Jan 18, 2003
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RIGHT BEHIND YOU!!!... Made you look.
Nov 4, 2004
#12
  • Nov 4, 2004
  • #12
joelliott said:
its just the opposite of underdrive pullies. It will turn your alt over faster at all RPMs. Thus increasing the amount of output your alt makes. its good for people with high volt needs like you. Id certainly get one.

I have a question about the wiring upgrade. I see alts on ebay like alterstart 160 amp etc. And they offer wiring systems to hook it up. Is thos the woring upgrade your refering to? Or is ther more? Thanks
Joe E.
Click to expand...

If you get the Alterstart 3G alternator, it'll have a slightly larger pully on it than stock. This will underdrive it a bit, but since it will be putting out more amps at idle, it won't mean much. You might want to get the next longer serpentine belt, because it's going to be real tight and tough to get on.

I got Alterstart's wiring upgrade, but was not real happy with it. It did not have an in-line fuse, and it was too short to reach all the way to the starter solenoid. I guess they expect you to run it to the battery.

I got a PA Performance upgrade kit and couldn't be happier with it.
 

TrickStang37

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Oct 17, 2004
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Nov 4, 2004
#13
  • Nov 4, 2004
  • #13
the 3g with the pulley it came with from alterstart would not give me full charge at idle with the lights on.
 

joelliott

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May 17, 2004
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Gainesville, FL
Nov 6, 2004
#14
  • Nov 6, 2004
  • #14
What Im looking to do is run the car as it is plus a small sound system. probably gonna be a US Acoustics 200W amp that runs on about 12.5V. 1 sub and a few other acc like radar detector, few interior neons, and fog lights (stock). Do you think a 130 alt would cover this? My cars an 85gt by the way. I noticed many places sell only 86+. Any tips as to a company that has the right stuff for an 85 stang? Thanks for yalls help.
Joe E.
 
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