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Another Battery relocations question..I just cant decide. help.

  • Thread starter Thread starter gruvee87vertgt
  • Start date Start date May 11, 2006

gruvee87vertgt

20+ Year Stangneter
Oct 7, 2003
272
26
28
Chicago, Il
May 11, 2006
#1
  • May 11, 2006
  • #1
well, I am relocating the battery this weekend.

where should I run the line from the solidnoid to the rear right side of the trunk?

should I go thru the passenger or driver side? should I run the wire under or in the car?

from the solidnoid should I run it along the firewall across to the passenger side or what?

any ideas or recommendations is recommended. thanx

also, I did alot of searching too.
 

Darkwriter77

Resident Ranting Negative Nancy
5 Year Member
Jul 1, 2005
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Apache Junction, AZ
May 11, 2006
#2
  • May 11, 2006
  • #2
Best to run the wire through the interior. Just route it through the firewall (I've got a big ol' grommeted hole for all my gauge leads, already, right next to the speedo cable hole), tuck it under the door trim and carpet, and run it up under the rear seat into the trunk area. Shouldn't matter which side you run it on, but I figure the driver's side would be a shorter route to the solenoid ... but then, if you're putting the battery on the passenger-rear, then I don't think it matters, either way. Just make sure there's no sharp surfaces or places where the wire could get pinched, and you should be fine.

I'm about to re-do the battery relocate, myself, since the prior setup wasn't NHRA-legal without a switch or officially-approved box, and my ground wire arrangement was kinda lame. The wiring diagram JRichker has posted several times gives a fairly good idea of how to wire things up, although I'm still fuzzy on which green wire, exactly, that I'm supposed to be splicing into and running back to the switch...
 

jrichker

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#3
  • May 11, 2006
  • #3
b] Rear mounted battery ground wiring. Follow this plan and you will have zero
ground problems.[/b]

One 1 gauge or 1/0 gauge wire from battery negative post to a clean shiny spot
on the chassis near the battery. Use a 5/16” bolt and bolt it down to make the
rear ground. Use a 1 gauge or 1/0 gauge wire from the rear ground bolt to a clean
shiny spot on the block.

One 4 gauge wire from the block where you connected the battery ground wire to
the chassis ground where the battery was mounted up front. Use a 5/16” bolt
and bolt down the 4 gauge engine to chassis ground, make sure that it the metal
around the bolt is clean & shiny. This is the alternator power ground.

The computer has a dedicated power ground wire with a cylindrical quick connect
(about 2 ½”long by 1” diameter. It comes out of the wiring harness near the
ignition coil & starter solenoid (or relay). Be sure to bolt it to the chassis ground
in the same place as you bolted the alternator power ground. This is an
absolute don’t overlook it item for EFI cars


Picture courtesy timewarped1972


Crimp or even better, solder the lugs on the all the wire. The local auto stereo
shop will have them if the auto parts store doesn't. Use some heat shrink tubing
to cover the lugs and make things look nice.

For a battery cut off switch, see
http://www.moroso.com/catalog/categorydisplay.asp?catcode=42225 is the switch
http://www.moroso.com/catalog/images/74102_inst.pdf
Use the super duty switch and the following tech note to wire it and you
will be good to go.

Use the Moroso plan for the alternator wiring and you risk a fire.
The 10 gauge wire they recommend is even less adequate that
the stock Mustang wiring.

There is a solution, but it will require about 40' of 18 gauge green wire.

Wire the battery to the two 1/4" posts as shown in the diagram.

The alternator requires a different approach. On the small alternator plug
there is a green wire. On the diagram it is #904, lt green/red wire that connects
to the alternator and dash light. It is the sense lead that turns the regulator on
when the ignition switch is in the run position. Cut the green wire and solder the
40' of green wire between the two pieces. Use some heat shrink to cover the
splices. See http://fordfuelinjection.com/?p=7 for some excellent
help on soldering & using heat shrink tubing.

Run the green wire back to the Moroso switch and cut off the excess wire.
Try to run the green wire inside the car and protect it from getting cut or
chaffed. Crimp a 18 gauge ring terminal (red is 18 gauge color code for the crimp
on terminals) on each wire. Bolt one ring terminal to each of the 3/16" studs.
Do not add the jumper between the 1/4" stud and the 3/16" stud as shown it the
Moroso diagram.

How it works:
The green wire is the ignition on sense feed to the regulator. It supplies power
to the regulator when the ignition switch is in the run position. Turn the
Moroso switch to off, and the sense voltage goes away, the voltage
regulator shuts off and the alternator quits making power.

See the following website for some help from Tmoss (diagram designer) &
Stang&2Birds (website host) for help on 88-90 wiring and lots more…

http://www.veryuseful.com/mustang/tech/engine/images/IgnitionSwitchWiring.gif

http://www.veryuseful.com/mustang/tech/engine/images/fuel-alt-links-ign-ac.gif

http://www.veryuseful.com/mustang/tech/engine/images/88-91eecPinout.gif

Diagram courtesy of Tmoss and Stang&2birds.
 

88_GT_5_oh

Sportin' a turbo 5.0 in Canadistan
Jul 4, 2004
1
0
1
WPG/MB/CA
May 12, 2006
#4
  • May 12, 2006
  • #4
subscribing..... i'm doing this only because i have no where to mount my msd box with my turbo on the passenger side, sooooooo the battery goes to the trunk

thanks for the info
 

jrichker

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May 12, 2006
#5
  • May 12, 2006
  • #5
Darkwriter77 said:
The wiring diagram JRichker has posted several times gives a fairly good idea of how to wire things up, although I'm still fuzzy on which green wire, exactly, that I'm supposed to be splicing into and running back to the switch...
Click to expand...
On the diagram it is #904, lt green/red wire that connects to the alternator and dash light.
 

Darkwriter77

Resident Ranting Negative Nancy
5 Year Member
Jul 1, 2005
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281
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Apache Junction, AZ
May 12, 2006
#6
  • May 12, 2006
  • #6
Aha! Cool. Much thanks.
 
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