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  • 1979 - 1995 (Fox, SN95.0, & 2.3L) -General/Talk-
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How hard to install another battery

  • Thread starter Thread starter jstang209
  • Start date Start date Sep 11, 2004
J

jstang209

20+ Year Stangneter
Jun 3, 2004
640
2
18
Stockton 209
Sep 11, 2004
#1
  • Sep 11, 2004
  • #1
due to my subs my battery meter always stays in the redzone, expecially with my ac on. Anyways how hard is it to add another battery to the trunk? and what all is really necessary?
 

Ray III

New Member
Feb 10, 2004
586
0
0
fixin Boomhower's John Deere in Troy, NY
Sep 12, 2004
#2
  • Sep 12, 2004
  • #2
you need a more powerful alternator, not more storage.
 

90mustangGT

I felt sorry for girls because
Founding Member
Jan 15, 2002
2,773
17
89
Dallas, GA
Sep 12, 2004
#3
  • Sep 12, 2004
  • #3
Ray III said:
you need a more powerful alternator, not more storage.
Click to expand...

Really, but let me elaborate. You need a 3G conversion, the 2G on there now sucks, takes too much rpm to get charge, product of 80's wiring, and only puts out 65amps. A regular 3G has better wiring, charges at a lower RPM, and regularly has 130amp output. You can get over 200amps though. There are a couple aftermarket companies which will sell you an even higher upgraded unit for not too much more. Get the -4 gauge wire along with it. You can get them chrome, pollished, or powdercoated different colors.

Check out www.4alterstart.com
and www.pa-perfromance.com edit

I have a 160A unit from alterstart, made a huge difference.
 

HISSIN50

"How long does it take to get help in here?
15 Year Member
Nov 29, 1999
31,179
33
129
Sep 12, 2004
#4
  • Sep 12, 2004
  • #4
well said. it would be like saying that "im running lean, so i will install 42# injectors" when in fact the fuel pump is only putting out 50LPH. a battery can handle all the juice you can toss at it (if the alt voltage regulator is working) - a better alternator is needed.

there are quite a few sites on doing the rewire - READ THEM ALL. some leave out important info. you gotta piece it all together, IMHO. upgrade motor grounds too.
the wiring kit Jason mentioned is absolutely necessary. some have pieced it together themselves - depends upon your comfort level with wiring. you dont want to catch the harness (or more!) on fire.
an alt from a 94-95 stang also works (if junkyard hunting).

good luck.
 

90mustangGT

I felt sorry for girls because
Founding Member
Jan 15, 2002
2,773
17
89
Dallas, GA
Sep 12, 2004
#5
  • Sep 12, 2004
  • #5
HISSIN50 said:
...upgrade motor grounds too...
Click to expand...

Good suggestion. Often an overlooked area.
 
F

fiveO92

New Member
Aug 15, 2004
13
0
1
Sep 12, 2004
#6
  • Sep 12, 2004
  • #6
do you have a capacitor with your system?
 
I

Idwitheld-1`

New Member
Nov 30, 2003
335
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0
Portland Oregon
Sep 12, 2004
#7
  • Sep 12, 2004
  • #7
fiveO92 said:
do you have a capacitor with your system?
Click to expand...


large capacitors only mask the problem.

1. Large Farad electrolytic capacitors have huge leakage currents.
2. ...will develop a voltage drop and not really help your problem (which may seem counter intuitive as people seem to equate capacitors to batteries)
3. Take up space....for little benefit.


Your best choices are:
1. Turn it down
2. 3G upgrade

I vote 1. Cheaper and less anoying to your neighbors.
 

90mustangGT

I felt sorry for girls because
Founding Member
Jan 15, 2002
2,773
17
89
Dallas, GA
Sep 12, 2004
#8
  • Sep 12, 2004
  • #8
Also, stock 15 year old gauges arn't internationally famous for thier accuracy.
 
J

jstang209

20+ Year Stangneter
Jun 3, 2004
640
2
18
Stockton 209
Sep 12, 2004
#9
  • Sep 12, 2004
  • #9
no i dont have a capacitor, i think ill just apgrade my alt.
 
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