Battery to trunk relocation suggestions?

[Dangerkitty]

I'm buying a new battery for my 240 and will be relocating it into the trunk.
Since I'm not stuck with buying a battery that fits into the stock location, what criteria should I use to decide which battery to buy?
weight is clearly an issue, but what about cranking power?

Any suggestions on which battery to use since it will be going into the trunk?

I'll be using a b230 turbo motor (if that matters)

Also, anyone sell a kit to relocate battery to the trunk?
(cables, battery box, mounting brackets)

Thanks
Thomas

[Mylesofsmyles]

Originally Posted by Dangerkitty

I'm buying a new battery for my 240 and will be relocating it into the trunk.

Any suggestions on which battery to use since it will be going into the trunk?

I'll be using a b230 turbo motor (if that matters)

Also, anyone sell a kit to relocate battery to the trunk?
(cables, battery box, mounting brackets)

Thanks
Thomas

Get a battery cable from a e30 BMW..it'll make the reach from the passenger butt cheek to the firewall on the passenger side, in the engine bay.

I've got my cable hanging out, waiting on my time and labor.

[JohnMc]

Summit sells a kit, but the battery box was too big to fit in my butt cheek. But it had plenty of cable to reach from there, under the carpet along the sill, through the firewall, over and down and along the engine harness, to the starter terminal.
http://www.summitracing.com/parts/SUM-G1200A/

I just used the same battery I'd had in the front, it was in great shap, nearly new, no reason to replace it. Got a smaller battery box at an outdoor supply place (in the boat section). I made a flat floor in the butt cheek by taking a short piece of plastic deck planking and shaving the ends a little, then drilling two holes theough the butt cheak and bolting it down. There's a strap on the battery box that goes around that.

I had to replace a small fuse box that was built onto the positive battery cable on my lete prod 240, with a new fairly heavy gauge wire that reaches over to the starter terminal. Also, the old negative ground terminal went from the battery to the engine block, with only lighter weight grounds to the body, obv. not a good idea to try and ground starter current through them so I added a ground strap under the hood (from crossmember bolt to engine block).

Missing battery! And new fuse box (with extra terminals for e-fan, MSD box, etc):

Battery box strapped down in the butt cheek. I wedged some styrofoam inside it to make sure the battery doesn't have room to wiggle around inside there. Ground goes to one of the bumper shock mount bolts (paint scraped, some nickel paste added).

[Dangerkitty]

Originally Posted by JohnMc

the battery box was too big to fit in my butt cheek.

Um, have to confess I laughed when I read that

Also funny that Summit doesn't provide the battery box dimensions in the kit description.

My car doesn't have full butt cheeks (78 GT) so it may be easier to get a box in there.

[Dangerkitty]

I guess what I'm really wondering is that since I'm not limited to a battery that fits into the stock location is there a criteria I should be using for deciding which battery to get?

Smallest and lightest?
Do I need a certain amount of cranking power?

[JohnMc]

Depends on if you DD in in the middle of cold, cold winter days or not. I think people get by with pretty small batteries. They make little bitty sealed batteres that weigh practically nothing, I think.

[Dangerkitty]

I am lucky to live in Northern CA and the car isn't my DD.
It will be my track day and autocross car once I get it all put together.

[kahluaTDI]

I would consider mounting it on the deck right behind the passenger seat, as that location is already flat, is easily accessible , and right over the axle.

[epjetta]

I have found the welding shop to be the cheapest place for new wire in large sizes. the ground wire is very finely stranded and it bends nicely around interior stuff when needed. and i just make a battery hold down out of perforated angle from the hardware store.

[Dangerkitty]

Originally Posted by epjetta

I would consider mounting it on the deck right behind the passenger seat, as that location is already flat, is easily accessible , and right over the axle.

That makes sense, but my butt cheek is flat and lower (lower than the mounting point you're suggesting) and I think that placing the battery back in the butt cheek will transfer more weight toward the back side of the car from the front.

[Dangerkitty]

.

[JohnMc]

It made a noticeable difference in traction in my car. That right tire used to be the go to guy for spinning and making black stripes, after moving 20 lbs (or however much a stock battery is) from the LF to RR corner it was more 50-50 on flat level ground.

[kahluaTDI]

Also, since you're getting a new battery, a Braile battery would do you some good, and being a race car the 7-8lb battery will help reduce weight as well.

Just remember, by running a battery into the rear of the car, you're negating overall weight reduction by running 15lbs of wire across the car. I love the idea of a rear mounted battery, but a small battery in/around the stock location is just as effective if not more.


Assuming as a race only car, it will be sitting most of the time, you're going to need a portable charger on hand after long spells of no track time, so there's really no reason to not go with the smallest battery you can.

[11110000]

Originally Posted by JohnMc

It made a noticeable difference in traction in my car. That right tire used to be the go to guy for spinning and making black stripes, after moving 20 lbs (or however much a stock battery is) from the LF to RR corner it was more 50-50 on flat level ground.

^ This.

I cut out my butt cheek and am welding in a flat panel to bolt in my battery box - over the right rear. I don't mind using a full-size battery back there since I've already removed so much weight from the back half of the car (carpets, sound deadening, butt cheeks, exhaust, heat shields, crash triangles, caliper brackets, underbody diffuser...)

Stock battery is ~40lbs of traction enhancer.

[Dangerkitty]

Originally Posted by kahlua240

Also, since you're getting a new battery, a Braile battery would do you some good, and being a race car the 7-8lb battery will help reduce weight as well.

Cool, thanks for the tip.
I looked at the Braille batteries and they look like a good option.

[doucheNozzle]

Why are you moving it at all? Buy a PowerXS battery and leave it in the stock location.

[Dangerkitty]

Originally Posted by scottyd

Why are you moving it at all? Buy a PowerXS battery and leave it in the stock location.

I guess the original idea behind relocating it was to move more weight onto the rear tires.

These look interesting.
http://www.braillebattery.com/index.php/

What is the advantage of the Power XS battery?

[doucheNozzle]

It's just much cheaper. Only 15lbs. Why do you want more weight on the rear tires?

[Dangerkitty]

Originally Posted by scottyd

It's just much cheaper. Only 15lbs. Why do you want more weight on the rear tires?

They might be a tad cheaper, but can't really tell.
When I go to their website they have a bunch of batteries listed, but no prices.
You have to click on each battery to find out what size/amps/weight/ect, and then click on the next one....
Guess I'll have to just call them on Monday...
http://4xspower.com/products/racing/road-course/

My thinking on relocating the battery was that the more the weight balance is distributed toward the center of the car, and the lower the weight is, that the better the car would turn.

[badvlvo]

Originally Posted by scottyd

Why are you moving it at all? Buy a PowerXS battery and leave it in the stock location.

That's what I did, XS power battery and bracket in the stock location. Saved 30lbs over the nose, no losses or weight from long cables.

It will eventually be mounted to the chassis brace like Ben did on his car.

[Dangerkitty]

Originally Posted by badvlvo

That's what I did, XS power battery and bracket in the stock location. Saved 30lbs over the nose, no losses or weight from long cables.

It will eventually be mounted to the chassis brace like Ben did on his car.

Do you recall which model XS battery it is?

[TestPoint]

I am installing a Ford 302 V8 into an '82 245. Planning on moving the battery into the right rear well for weight front/back issues. Got a 20' welding cable in hand. Going to install a 300A fuse block at the new battery location and a marine battery box.

Two questions:

I had planned on routing the cable the cable across the wagon under the floor, through the fuel line hole and forward to a Ford Battery Junction Box mounted on the left front wheel structure. Looks like JohnMc ran the cable under the carpet along the right side. Is it visible from inside?

JohnMc mounted the marine battery box on a plastic deck planking. Would you post a picture of how you mounted that please?

[towerymt]

Odyssey PC680 or Braille 11.5lb or Deka equivalent. I would mount it on the raised part of the trunk above the axle. On its side. That's where mine has been for years.

[M.H. Yount]

I used a plastic battery box from Wally World; mounted in the passenger side spare tire well much as John did on the wagon above; grounded in the trunk (scrape paint, serated washer for some 'bite'); bought a set of 2 gauge jumper cables, removed the clamps and joined the two cables together in the lug - so a double-2 gauge cable running to the front. Seems to have worked well - but only an 8 year test so far. ;)

As far as shifting weight around, if you play around with moving stuff and have access to scales you'll see some interesting effects. How far ahead of the front 'axle' line it was vs. how far behind the rear axle you move it gives you some leverage on the weight shifting if you desire that. So if you move it further behind the rear axle than it was in front of the front 'axle' you get an even greater shifting of static weight from front to rear on the scales. Putting it in the well is about as low as you can get it from a CG perspective -- but hanging it out back increases the polar moment ---- you can play lots of physics games when you start moving stuff around.

My goal was simply to shift a bit of weight to the rear to help offset the heavier motor and to make room for a cold air box on the passenger side front. So - the battery went to the back and the windshield washer went to where the battery was. And the cold air box went in the passenger front corner.

[Turborg]

Originally Posted by Dangerkitty

I am lucky to live in Northern CA and the car isn't my DD.
It will be my track day and autocross car once I get it all put together.

I surprised nobody has mentioned the dangers of having a non sealed(vented) battery in the trunk or in the backseat or back of a 245(like a hydrogen gas exposure/explosion). I have a 800 cold cranking amp red top Optima battery installed in the passenger side buttcheek, mounted on its side. The panel that covers this area installs without touching the battery. I didn't think it would make much handling difference but it did make a noticeable difference. I only ran the hot to the starter and grounded the battery on the big frame bolt by the buttcheek, and I have zero problems the install. I just got a free one on warranty because I left the lights on one too many times and totally drained the battery. I have a switch to shut the battery off but have never installed it. Does make it convenient for working on the car