RE-relocating the battery?

[Darkwriter77]

Being that my battery was relocated to the trunk before I obtained it, and I'm not wanting to wrestle with installing an external ignition switch just to meet NHRA tech specs, and a slew of other reasons, I'm considering the project of putting the battery back up front where it originally was located. I'm not terribly worried about changing handling characteristics, as I'm not doing any autocrossing with the car, nor is traction going to really change much - heck, I'll probably leave that current battery back there for dead weight, anyway (until I drop in a full-size spare tire), and install a proper Group 58 size battery up front, anyhow.

Trouble is, I have no battery tray left up front, I'm not sure where the ground cable originally was located on the front end, and I have no idea how I'm going to make the thing sit securely without flopping all around in there, short of employing some ugly and awkward metal strapping, or something like that.

It wouldn't be such a confusing issue if I'd been the one to do the relocation, myself, in the first place but, again, this was all hacked and bolted into place long before I got hold of it.

Oh, and a side-question: Would I be able to salvage the big ol' thick welding cable they used to put the battery in the trunk for use in doing the 3g alternator upgrade?

 

[jrichker]

A battery tray from almost any late 80's or early 90's Ford would probably work. There are two boltholes on the lower LH side of the tray that secure it to the chassis.
1.) The main power ground is from engine block to battery: it is the power ground for the starter & alternator.

2.) 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.

3.) The computer has its own dedicated power ground that comes off the ground pigtail on the OEM style battery ground wire. It is a black cylinder about 2 1/2" long by 1" diameter with a black/lt green wire. The wire goes into the harness at the starter solenoid.

4.) One of the pigtails on the negative battery cable gets bolted to the chassis ground near the starter solenoid.

Any leftover heavy gauge wiring from the trunk mounted battery would be OK to use for the 3G power & ground wires. They may be a little stiff to bend them around things, but electrically they are good.

 

[Busted07]

Maybe i misread this, but let me get this right... you dont want to install a cutoff switch, and youd rather buy another battery, rerun all of the wiring, and leave the other one back there? if that what i just read, i think you completely contradicted yourself. putting in a cutoff switch will take 1/4 of the time it will take to redo all of the wiring, and if youre leaving the battery back there anyways, why put another 40 pounds of battery up front?


im sorry, i just dont see any logic in this at all... maybe i misinterpreted it, but it sounds like you want to do a hell of alot more work so you dont have to install a cutof switch

 

[Darkwriter77]

Reasons being:

1. I don't have anywhere to really mount the switch without it looking hideous and/or giving some joker a means of messing with my car in a parking lot. (Come outside after work to start the car, but some A-hole's shut off the battery, all my radio presets are gone, ECM has been reset, etc.) Unless there's some kit for sale that allows the switch to be behind the license plate - the one I've seen was, I think, a custom-made job - then there's not many options there;
2. I'd need to invest in a fancy-schmancy battery box and/or a bunch of sheetmetal to place behind the back seat to make it NHRA legal;
3. I'd only intend to keep the old battery in the back for weight until I can score a full-size spare tire, which would weigh *approximately* the same as the battery that I have. Soon as I have the spare in, the battery comes out;
4. The battery that's in there is aging enough that it's about due to be replaced, anyhow.

I know it sounds a bit dumb and odd - hey, I'm all about being dumb and odd, anyway - but I can't really justify the bodywork AND the cost when I can just rearrange what I've already got and be done with it.

So, aside from the main ground to the block and the pigtail to the chassis, the only other cable would be just a short jump from the battery's positive post to the starter solenoid, right? Cool beans. Now to see about rigging up some kinda tray for the battery to sit in, maybe using this groovy homemade aluminum half-box someone left for me in the battery core bin at work...