[Guest]

Battery Relocation

Has anyone relocated their battery, and if so, where did you put it. I would think you should be able to fit it in the gastank area with a relocation kit (currently looking online for one). I have the spare tire and everything already removed so space shouldn´t be an issue, and also I would switch to one of the gelcell style batteries to battery acid or fumes wouldn´t be an issue. I would think the relocation would be a noticeable increase in handling since the stock location is WAY out there. Let me know what you think.

 

[Guest]

The only problem I see with this is mounting the battery in that area. You really need to bolt the box or mounting bracket down and there isn´t much clearance to be able to move the battery into place. Power wire should be easy enough to run up to your starter or a distribution block. I just got done doing it on my Audi a few weeks ago, but it has a trunk and a very nice pocket that is the perfect size for my optima.

Make sure to solder the ends, don´t just crimp them, and add a dielectric grease to keep it from coroding wherever you have a connection.

 

[Guest]

Hi, Keep us posted on your project. Since the GT is nose heavy to begin with, it makes alot of sense, and could improve handleing.

 

[Guest]

Funny you should bring this up, CoolBlue, I did this battery relocation just last month, and almost exactly the way you proposed. Congratulations, because it works very well. Picked up an Optima red-top (800 CCA), locally for about $115, a compression-fitting battery cable kit thru the Eastwood Co. for $40, and an AutoZone battery box ($15), so it wasn´t really that expensive a project. These gellcell batteries are worth the money, IMHO. . . I made another plywood spare-tire platform that extends about 14" further back into the tail of the car-- don´t get too close to the taillights, right?-- and notched around the fuel filler tube. Of course, the battery is in the right rear corner. . . the traditional performance location.

 

[Guest]

Should probably mention that the project was inspired by the fact that the battery tray in the nose of this GT was completely rotted away, and I wanted to see how this transfer of weight would improve handling. It DOES. One minor point to consider on this, though. . . if you have an elaborate stereo system in the car, as this one does, keep in mind that your power source is now on the OTHER side of the firewall, so plan on spending some time rerouting your wires.

 

[Guest]

Right on opelmark. Did all the research for me already.
So did you just make some brackets attached to the plywood to hold the box down? Also, are you using a sealed box (I think usually called marine box or for marine use)?

 

[Guest]

OpelMark, are you concerned at all about having the battery in such a close proximity to the gas tank? I mean, you´ve got the dynamite AND the match in the same compartment! I cut off all the rear sheet metal on my old man´s GT, and the car had sustained a light hit once before...it bent the gas tank in 4 inches in one area, it made me nervous. So I tubed-out the rear section for impact protection, tying it into my rollbar I had already welded in. I instead placed the battery (yellow-top Optima because the red-tops don´t tolerate a full discharge) in the right rear of the back *seat* area. I recessed it into the floor to help keep the center of gravity low as well, and it is in a marine battery box too.

Bob

 

[Guest]

So you put the battery basically underneath the flat area behind the seats, or just behind the passenger seat (limiting the amount the seat can come back)?

 

[Guest]

It certainly crossed my mind, Bob, that getting rear-ended by anything heavier than a bicycle could be grim indeed . . . but driving itself is not without risk, and I chose to drive a car that doesn´t do well in accidents in the first place. . . I´m out here in the land of the half-ton truck (and bigger), and in a major crash I will probably DIE. But what a way to go, Opeling to the bitter end Your point is taken, though, and anything done to the car can be undone. I´d rather armor the rear end of the car than use the carpeted shelf behind the seats for the battery, but given the choice between that and a spectacular explosion . . . you get the idea.

 

[Guest]

So you put the battery basically underneath the flat area behind the seats, or just behind the passenger seat (limiting the amount the seat can come back)?

*****It´s not directly behind the passenger seat, but rather where the wood "shelf" is behind the front seats. I made the shelf area custom out of 1/2" plywood covered with trunk carpeting and it´s split into left and right sections, plus left and right vertical partition sections. These are retained by roller catches, so they "snap" into place. The battery is not resting on top of the shelf, instead the shelf has a hole cut into it and the battery sits on the floor of the car. The ground strap is attached to a stainless bolt welded directly to the body, and also under the shelf is another fuse box for accessories. The driver´s side "shelf" has a space under it for a tool kit and other spares.

 

[Guest]

Opelmark, I was just concerned with the safety of the battery location, that´s all. Of course, nothing is perfectly safe, for that you´d have to stay home in bed...but there are worse things than dying in a car crash. Surviving a fiery crash seems to be one of them, fire has to rank right up there with my worst fears in a car wreck. I´ve seen a lot of friends of mine survive high speed racing crashes and keep right on racing, but one small burn is all it takes for most people to quit. Scary stuff.

 

[Guest]

Ouch. Even the thought of it hurts when you put it that way. . 8o It would be hard to appreciate a minor handling improvement laying on one´s back in the burn ward, no question, & I appreciate your pointing that out. One needs to consider that not all of his passengers are ready to die, or be disfigured, for his GT to corner better. . .that´s what I´ve just been told. Just NOW, matter of fact. She´s standing here, scowling, as I write this . . .On your Dad´s car, How far does the battery box protrude from the "shelf" behind the seats? I like the idea of welding the ground strap to the body, also, so may just mount the battery as far to the right as possible, and as low as possible, as you did.

 

[Guest]

The battery sticks up about 4.5" above the rear "seat". I could have cut out the sheet metal floor and recessed it more, but the car is getting a 2.7 litre stroker and the exhaust will be 2.5" with a large muffler to quiet it down...space below is at a premium. As it is I have to run the pipe though the tranny tunnel (over the tranny mount in fact), in order to give adequate ground clearance. The car was lowered almost 3".

On my Manta hillclimb car, I did exactly this, recessing a Miata-type (small Westco) battery into the floor area below the back seat. It sticks up about 1.5", and hangs down about 1/4" ABOVE the torque tube crossmember, so it´s not the lowest point of the car by any means.
Hope this helps. Hopefully when I get my new computer figured out I can start taking digital photos to show this stuff rather than trying to describe it.

 

[Guest]

I also plan to relocate the battery to the rear area, but will use the aftermarket battery from my now defunkt Miata. I bought a Westco battery a few years back to replace the 6 year old stock battery. It is completely sealed and was accually smaller than the stock one. It measures 7 1/2" wide x 5" deep x 8" from the bottom to the top of the posts. www.westcobattery.com has a newer version of the same battery that now has no free liquid electrolyte. It weighs 25 lbs. and has 475 cranking amps with a price tag of $84.95 shipping included. If interested, it is Westco battery # 12v31m or select Mazda Miata from the products pull-down menu on the home page. I will also be "borrowing" the stock wiring that runs into the trunk. If anyone is interested in the harness, I can call the wholesale dealer I used to go through to find out how much one costs.

 

[RallyBob]

Here's where I've relocated the battery to in a GT. It rests on welded bracket on the floorpan. Hold-down studs are welded in place, and the top hold-down bracket is aluminum (custom). Ground stud is a stainless bolt welded to the chassis. There is also an auxiliary fuse box under the rear "seat" panel for accessories. Both sides of the upper and lower seat panels are retained by spring-loaded clips, and are easy to access.

Bob

 

[willyrick]

I am thinking of moving the battery from the front of my 73 GT to the right rear corner using an Optima sealed battery. Has anyone done this? What are the risks involved?
Thanks, Rick

 

[RallyBob]

Go to the 'Performance' section, and look in the archives. One of the first 'heated' threads months back was this exact discussion.

Bob






Threads Merged

 

[willyrick]

Thanks for the response Bob. I had actually done that last night, and is also why I posted this query. I was hoping that someone would post an update. I see what you have done with the shelf location and think that I understand why. I was hoping to hear from those who might have chosen the riskier approach.

Some questions I have:

Is there a way to enclose the battery over the gas tank so that the risk is somewhat mitigated?

What is the main risk, collision induced shorting or acid leakage?

Is there a product that incorporates an inline master fuse or breaker right at the post?

Has any one run an Optima (or other gel style) on its side for a long period of time?

 

[Legba6]

This may or may not help you out, but have you considered a dry cell battery. The application for automotive use is kinda new and there are only a select few companies that manufacture them, but I hear they work well and are very light.

 

[RallyBob]

Is there a way to enclose the battery over the gas tank so that the risk is somewhat mitigated?

What is the main risk, collision induced shorting or acid leakage?

My fear is very real here. How many GT's, at one time or another, have had gasoline fumes inside the car because of dried out/broken/disconnected vent hoses? All it takes is a loose battery terminal and a spark in born.....

IF you decide to mount the battery on top of the fuel tank, then you must take these factors into consideration:

**Must have ABSOLUTELY no fuel leaks or fuel vapor leaks
**Battery must have insulated terminals
**Battery must be in non-conductive battery box, and the box and battery must be securely BOLTED down. That cheesy strap that is designed to hold the cover in place will NOT hold the battery down in ANY sort of accident or severe road maneuver, and if it moves and the cables get pulled from the battery, it WILL arc and probably cause an explosion.

I got to see a battery explode firsthand from exactly this scenario, it was strapped into a pickup truck bed, the driver took a sharp turn and the strap broke, then the cable pulled out and the battery exploded. There was acid and little pieces of plastic everywhere.

Bob
'Safety is no accident'