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Ground Wire Location *HELP* - Pic Included

  • Thread starter Thread starter stussy2870
  • Start date Start date Apr 8, 2020
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stussy2870

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Apr 8, 2020
#1
  • Apr 8, 2020
  • #1
Folks,

Im redoing just about everything in my interior which includes "Fixing" the wire run for my Trunk mounted battery. The PO ran both Positive and Negative wires from the trunk all the way back to the Engine Bay - UNDER the car. They were connected as follows:

Pos to the Solenoid
Neg to a bolt on a bracket near the Timing cover.

From there, there was an additional negative wire from the AC bracket to the body ( in the engine bay near where the stock battery was) See pic.

My Question are:
1) can i mount my negative here (See pic with Finger) - i will of course wire-wheel off any paint
2) do i need to connect a second Block to Frame/Body where the original one ran to or do i just abandon that location?

Any answers and Pics of your set up would be GREATLY appreciated..
 

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90sickfox

Wasn't a pretty sight...and I've got big hands
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Mar 2, 2015
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Apr 8, 2020
#2
  • Apr 8, 2020
  • #2
That metal is too thin for a good ground. I run my grounds to the sway bar mounting location below the battery. I run a cable from there to the body...and one from there to the engine. Helps keep the wires out of view too.
 
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stussy2870

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#3
  • Apr 8, 2020
  • #3
90sickfox said:
That metal is too thin for a good ground. I run my grounds to the sway bar mounting location below the battery. I run a cable from there to the body...and one from there to the engine. Helps keep the wires out of view too.
Click to expand...

I think i may be misunderstanding this - you run your negative to the sway bar in the Rear - then to the body- then to the engine?

Remember, im already IN the trunk - im trying to avoid running 2 wires back to the engine bay - just want to know where i can safely Ground my battery (in the trunk area)...
 

90sickfox

Wasn't a pretty sight...and I've got big hands
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#4
  • Apr 8, 2020
  • #4
The best way to ground the battery is up front. You need some pretty substantial metal to get a good ground in the rear. Some people run a wire through grommet in spare tire well or the area where the fill neck is to the location where the quad shocks mount to the frame ( behind right rear tire ).

I miss understood what you wanted. For the engine and battery I run a ground strap at rear of head or intake bolt stud to firewall, from water pump or PS stud to front sway bar bracket mount, from bracket mount to battery, and a smaller wire from battery to computer ground location ( where your pic is ). I use the battery cable that comes the battery post clamp and another smaller gauge black wire.

A bunch of people get slow crank issues when grounding to stuff in the rear. The best way is to run both positive and negative the full length of the car. This has been debated here over the years...and is still up to debate. Several members run the ground to a welded on stud and have success. Some ground to a seat belt bolt and it works for them. I can only speak of the ways I've seen it work with my own eyes.
 
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stussy2870

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#5
  • Apr 8, 2020
  • #5
Understood - thanks so much for taking the time to answer. All of those posts -including my own- have my head spinning.. I think ill just run both .. again..
 

Blown88GT

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Nov 13, 1999
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Palm Beach Gardens, FL
Apr 8, 2020
#6
  • Apr 8, 2020
  • #6
90sickfox said:
That metal is too thin for a good ground. I run my grounds to the sway bar mounting location below the battery. I run a cable from there to the body...and one from there to the engine. Helps keep the wires out of view too.
Click to expand...
Too thin for a good ground? Please explain.
 

90sickfox

Wasn't a pretty sight...and I've got big hands
SN Certified Technician
Mar 2, 2015
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Apr 8, 2020
#7
  • Apr 8, 2020
  • #7
Blown88GT said:
Too thin for a good ground? Please explain.
Click to expand...

That's kind of self explanatory.

The battery should be grounded to the thickest metal you can find on the car. I personally had issues grounded to a belt bolt. It wasn't enough ground for my battery to properly crank the starter. Ran the cable to the engine ground junction and issue went away. That bracket location for the quad shocks works. I'm sure there are other ways. I want to avoid the OP from being frustrated with slow crank and charging issues.

What metal back there is good enough for a decent battery ground ? Please explain
 

Blown88GT

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Apr 9, 2020
#8
  • Apr 9, 2020
  • #8
That piece of metal will easily handle starting currents of 600 amps. It's the resistance at the attachment point that could be a problem.

Here's the best way to connect a rear mounted battery.
 
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90sickfox

Wasn't a pretty sight...and I've got big hands
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Apr 9, 2020
#9
  • Apr 9, 2020
  • #9
That's one thing people always forget....the fuse in the positive wire.
 
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stussy2870

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Apr 15, 2020
#10
  • Apr 15, 2020
  • #10
I know lots of folks use/say to use "Welding wire".. can i use this wire? Wiring will be run IN the car, Through the FW out the Drivers side FW.

Amazon product ASIN B01MXRVKLBView: https://www.amazon.com/InstallGear-Gauge-Black-Power-Ground/dp/B01MXRVKLB
 
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stussy2870

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Apr 5, 2019
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Apr 15, 2020
#11
  • Apr 15, 2020
  • #11
Blown88GT said:
That piece of metal will easily handle starting currents of 600 amps. It's the resistance at the attachment point that could be a problem.

Here's the best way to connect a rear mounted battery.
Click to expand...

Wow.. thats not really even close to what i have.. or what i thought i wanted to do.. If im running 2 wires back to the engine bay.. ill just reconnect to the original connection points..
 
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