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65 Battery Relocation

abrahamfh

Active Member
What is the benefit of relocating the battery to the trunk?

If someone would decide on doing the battery relocation, is there a RS fender apron that would match the LS front fender apron to keep the engine compartment looking uniform?

I just think it would look weird having a fender apron with the location to put the battery even though it is in the trunk.
 
That spot where the Batt. was is where I put my BEER while I'm working on the car. Keeps it from getting spilled or stolen.
 
Agree with Steve, I had to replace my rusted out battery tray area due to the previous owner using it for a battery shelf rather than beer storage:
IMG_2075.jpg


While moving the battery does remove 40lbs + off the front end and places it above the driven axle for traction the main reason if for the BEER SHELF it creates.
Jon
 
The benefit of moving the battery is weight distribution from a nose-heavy car to a less nose-heavy configuration. 55 pounds reduction forward of the front wheels to behind the rear wheels is a simple but highly effective means of putting more weight to the rear for traction. It also helps drivability in snowy conditions, necessary when Hell freezes over in SoCal.
 
Just keep in mind you then can't put so many ex girlfiends in the trunk if you fill it up with batteries.
 
Or you could drop the weight to under 17lbs and still have a flat shelf for beer:

s680.jpg
 
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I used the space to mount my coil and MSD box. Not that a non running engine needs those things :roul



6671600055_large.jpg
 
To avoid the loss of battery/cranking power in a trunk battery, what gauge wire should be used? Is there a benefit to mount the solenoid in the trunk? Anti-theft?
 
Some mount the solenoid in the trunk, I left mine in the stock location. IIRC, I used O gauge wire. Wrapped in protective wrap and run inside garden hose anywhere it might rub edges..

I also have a main kill switch mounted in the back.
 
"abrahamfh" said:
What is the benefit of relocating the battery to the trunk?

You die faster when the gas tank blows up? :shrug LOL

My battery is in the trunk currently and I'm still 50/50 if I want to relocate it back to the front, so feel free folks to post more pro's & con's of front vs rear batteries! :thu
 
I am moving the battery in Ed because of a weight distribution thing, it is kinda a GT350 clone and I am going to add a battery and use a marine battery switch that will allow me to run on right, left or both and shut the power off.


This will give me some security and if the battery runs dead, I can twist the switch and start my car from the other battery.

Dave from the other forum (from Fresno) is running it this way on his 70.

Mel
 
Most of the installs I've read suggest 1/0 welding cable. If you put the solenoid in the trunk you can avoid having a constant hot wire running the length of the car. When wired correctly the 1/0 wire is only hot during cranking.
Here's one way of setting it up, the diagrams at the bottom can be placed next to each other to make more sense:
http://madelectrical.com/catalog/tm-1.shtml
Jon
 
"Jonk67" said:
Most of the installs I've read suggest 1/0 welding cable. If you put the solenoid in the trunk you can avoid having a constant hot wire running the length of the car. When wired correctly the 1/0 wire is only hot during cranking.
Here's one way of setting it up, the diagrams at the bottom can be placed next to each other to make more sense:
http://madelectrical.com/catalog/tm-1.shtml
Jon

I understand the to eliminate the constant hot cable with a trunk mounted battery. However, I don't see too much advantage of putting the solenoid in the trunk. Yes, you eliminate the constant hot cable from the battery to the starter, but you still have a constant hot cable running from the alternator to the battery?

What am i missing?
 
I carried out this Mod on my car and I replacedd the inner fenders as i was ripping out the shock towers for the R&C setup.

I am also running two cables to the front of the car instead of earthing to the trunk.

"Kats66Pny" said:
You die faster when the gas tank blows up? :shrug LOL
Not if you are using a dry cell battery like an optima red or yellow top.


Here is a guide for doing it on a 65
http://www.midnightdsigns.com/Mustang/Battery.htm


I am also installing a dead mans in the trunk and another secert one for the earth.

DSC02325-1.jpg

DSC02323-1.jpg
 
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"garner67" said:
I understand the to eliminate the constant hot cable with a trunk mounted battery. However, I don't see too much advantage of putting the solenoid in the trunk. Yes, you eliminate the constant hot cable from the battery to the starter, but you still have a constant hot cable running from the alternator to the battery?

What am i missing?

I've got the battery and solenoid in the trunk. I have an unfused 1/0 cable running up to the starter and a 2 ga. with a 175amp mega fuse running up to a distribution point under the dash that feeds the main fuse panel and my relays for fan, EFI and lights. The alternator actually connects to that distribution point under the dash as well.


The reason this is safer than not having the solenoid in the truck is that the starter cable can't be effectively fused due to the high amp draw when you start the car... well.. I suppose you CAN fuse it but the size of the fuses would be ridiculous and would actually OVER protect your system in most situations other than starting. So essentially, I'm avoiding having to run an unfused, always hot cable, with lots of amperage running the length of my car.

-Shannon
 
Sure sounds like a lot of work just to distribute the weight of a battery and if you have a fastback, you are giving up very precious real estate in them small trunks. Talking about junk in the trunk?
 
For me it was less about weight distribution and more about having a place to put the air filter for the EFI intake... The weight reduction in the front is just a bonus.

-shannon
 
Aside from the obvious rear weight gain moving the battery to back provides, the larger benefit (at least to us straight line guys) is a big weight loss in the front end. This allows the front to rise that much faster upon acceleration the net affect being greater "weight" transfer to the rear. This results in increased force to the pavement providing increased traction...theoretically anyway. Same reason you use lighter front springs and shocks.
 
Well, I'll chip in here. Like others, I put it back there to gain real estate for modern wiring & such (ignition module, fuses for new light relays, etc) as much as weight distribution.

I did not put the solenoid in the trunk. Lots of factory cars run batteries in trunks w/o the solenoid back there. Properly protect the wire and it's not an issue. Also, as pointed out, you have to run a pretty big cable back there to charge / provide power when not running.

However, I used 2 ga wire from the trunk to the solenoid, and 2 ga from the solenoid to starter. Anything larger is overkill, IMO - adds weight and cost.

2 ga gives a theoretical voltage drop with a 250 amp starter draw of .5 volts. I measure less than that - .3 volts when cranking - even with my old, outdated, almost worn out original starter. Anything less than 10% drop on a starting circuit is acceptable according to what I've read. Switch to a modern PMGR starter and the drop will be so low you will not be able to measure the voltage drop accurately with a standard meter.

Heck, I crank a high compression 454 boat engine through 20 feet of 2 ga with no problem. A little SBF won't bother 2 ga wire.
 
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