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alternator, what should i get

  • Thread starter Thread starter legalize420
  • Start date Start date Aug 10, 2005

legalize420

Active Member
May 21, 2005
1,541
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37
South Florida
Aug 10, 2005
#1
  • Aug 10, 2005
  • #1
i have pullies and 2 10's in the trunk. volatge is fine without ac on. with ac on sitting at a light it drops quite a bit until i start going. would getting a bigger alternator solve my problem. what are the amps on the stocker. how much more amps would i need. thanks
 

bubba-dough

Active Member
Dec 28, 2004
1,044
2
38
Indiana
Aug 10, 2005
#2
  • Aug 10, 2005
  • #2
Yes a bigger alternator would solve that prob. The stock one is 75 amp and at idle output is something between 20-25. Your amp(s) are probably pulling most of that. http://secure.50resto.com/category.cfm?SID=1&Category_ID=575 Iwould recommend the 130. The PA Performance ones are lifetime warranty.
 

jrichker

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Mar 10, 2000
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Dublin GA
Aug 10, 2005
#3
  • Aug 10, 2005
  • #3
Do a 3G installation. The 3G's are a 130 amp alt, the most common one used is from 94-95 Mustangs.

Here's websites with pictures of the 3G installation...

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 installation

Use these sites for information on 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 will be overloaded to the point of catching fire and burning up the wiring harness.

The secondary power ground is between the back of the intake manifold and the driver's side firewall. It is often missing or loose. It supplies ground for the alternator, A/C compressor clutch and other electrical accessories such as the gauges. Any car that has a 3G alternator needs a 4 gauge ground wire running from the block to the chassis ground where the battery pigtail ground connects.

Electric fan = 3G alternator if you want long life & reliability from your car.
The electric fan saves some HP. The stock fan's parasitic drag runs from 7-12 HP depending on who you talk to. The electric fan uses about 1/2 HP of power from the electrical system.

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 @ $3.90 each (need one) http://www.partsexpress.com/pe/showdetl.cfm?&DID=7&Partnumber=071-952

Fuseholder @ $5.80 each (need one) http://www.partsexpress.com/pe/showdetl.cfm?&DID=7&Partnumber=263-630

4 gauge black wire @ $1.25 a foot (use string to lay out routing & determine length) http://www.partsexpress.com/pe/showdetl.cfm?&DID=7&Partnumber=100-196

4 gauge red wire @ $1.25 a foot (use string to lay out routing & determine length) http://www.partsexpress.com/pe/showdetl.cfm?&DID=7&Partnumber=100-194

4 gauge ring crimp terminals (package of 5) $3.25. http://www.partsexpress.com/pe/showdetl.cfm?&DID=7&Partnumber=095-584
 
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