Relocate battery

[Robert986]

I just purchased a Odyssey PC925 to reduce weight. When I´m about to put the new battery in I cant help but thinking of how high the battery box is located. The PC925 is considerably lighter than the original, but is still a respectable weight. Wouldn´t it be great to place it at the bottom of the frunk to lower COG... Hmmm cant hurt.

So I start looking at how to fasten it and how to relocate the wires.. Strange thing, I found absolutely no example of others on the forums performing this operation.. Is it just me?

[mikefocke]

So what would you give up. Trunk space? The spare tire? A simple connection? Dangling wires?

[boxfix]

IT is just you!!!! ;-)

Make so little difference in CG and lots of headaches.

[Meir]

Extending the battery wires is always a bad idea.
You will interduce unnecessary resistance to the power distribution.

[paulofto]

Had the Porsche engineers thought that the battery should reside lower in the body they would have done it. A lot of work for likely no improvement.

[Topless]

It's just you.

The battery location was carefully chosen on the centerline of the car to protect it in an impact so the car doesn't catch fire with you in it. The rest of the car will be sacrificed yet the battery, fuel tank, and passenger compartment are well protected.

[itsnotanova]

Spec boxster's have to keep the battery in the stock location but almost every other type of boxster or 996 race car I've seen moves it to a lower position in the car. The optimal place on a boxster is in the passenger foot well from what I've heard. A lot of them move it down in the frunk. That's where I moved mine and I put it right in front of the spare tire. You're only extending the cables 2 feet at best. That won't cause electrical issues. Heck, people have been relocating batteries to the trunk for decades. Many many vehicles have the battery located in a very vulnerable spot with only a little bit of sheet metal protecting it. I've bought quite a few cars where the battery was crushed in the accident. No fire. If you don't believe me, go on copart.com and you'll see thousands of cars/trucks with crushed batteries and no fire

[Robert986]

Wow, great response!

Thanks all.. I´m not to concerned regarding the safety aspect, and if I´ll do it it will need to be a very neat installation, no cheesy Cables hanging around.. I guess it all comes down to wether I should prioritize this before all other stuff I plan to do on the car this Winter. Still if someone has done it, it would be very nice to se some pics or get some hints.

If I go ahead I´ll show & tell :-)

Edit: To answer a previous question: I have already given up the spare and replaced it with a small compressor/repair kit.
A lot of effort for very Little improvement is my trademark ;-)

[itsnotanova]

If you go on here Woody's build thread with google chrome you can see some pictures of my install.

[Boxstard]

Maybe you install that lighter battery you got and see if it makes appreciable difference to you. If not, probably you won't notice much difference moving it down to the frunk floor and you can prioritize other things.

I like the way it is installed, protected from impat and weather. With 914 they installed it in the engine bay half exposed to the environment so it spits acid right over the longitudinal frame to corrode it.

[j.fro]

My solution. Of course, I've also dumped all of the trunk interior, etc. Part off the goal was to try to balance out the brake booster. The car is naturally driver side heavy.

[BOOTLEG]

Nice!
Think I will do this.

[itsnotanova]

If you look at the bottom of the frunk in J.Fro's picture. Those two rubber plugs come out easily and make a great vent for the battery tube

[BYprodriver]

Originally Posted by Robert986

Wow, great response!

Thanks all.. I´m not to concerned regarding the safety aspect, and if I´ll do it it will need to be a very neat installation, no cheesy Cables hanging around.. I guess it all comes down to wether I should prioritize this before all other stuff I plan to do on the car this Winter. Still if someone has done it, it would be very nice to se some pics or get some hints.

If I go ahead I´ll show & tell :-)

Edit: To answer a previous question: I have already given up the spare and replaced it with a small compressor/repair kit.
A lot of effort for very Little improvement is my trademark ;-)

I have a aluminum sheet mount for a Odessey 925 for sale if interested in buying

[stephen wilson]

Originally Posted by itsnotanova

That's where I moved mine and I put it right in front of the spare tire.

You went to the trouble of relocating the battery and you still have a spare tire in the trunk ?

[Robert986]

Originally Posted by BYprodriver

I have a aluminum sheet mount for a Odessey 925 for sale if interested in buying

Thanks! However I live in Sweden so I guess its a bit far :-)

[Robert986]

I found a "Heavy" metal plate under the battery, thought that I could remove it to save a few grams.. Then realized that it is probably vital to keep the gasoline pump assembly safe in case of an accident, so this plate will stay in Place.

[Robert986]

Maybe a step away from the main topic, but.. When relocating weight, I Believe we all can agree on that low is good. However do we have consenus regarding:

1) Center of mass (I Think it´s called).
I find the box to be very agile in turns, this is nice as long as you stay in Control, but when you go over the edge the Quick behaivour related to high amount of mass in the center also makes is easy to spin around..

2) Balance front/rear.
Some say... (And this time not related to The Stig) That the 911 is quicker also due to the weight distribution:
a) Better balance front/rear when breaking.
b) better grip on acceleration.

So.. How does this affect the aim of relocating weight in a Boxster? Shold we strive to relocate as much weight as possible to the back trunk?

[BYprodriver]

Originally Posted by Robert986

Maybe a step away from the main topic, but.. When relocating weight, I Believe we all can agree on that low is good. However do we have consenus regarding:

1) Center of mass (I Think it´s called).
I find the box to be very agile in turns, this is nice as long as you stay in Control, but when you go over the edge the Quick behaivour related to high amount of mass in the center also makes is easy to spin around..

2) Balance front/rear.
Some say... (And this time not related to The Stig) That the 911 is quicker also due to the weight distribution:
a) Better balance front/rear when breaking.
b) better grip on acceleration.

So.. How does this affect the aim of relocating weight in a Boxster? Shold we strive to relocate as much weight as possible to the back trunk?

I believe so, to reduce under steer & improve traction for rear tires.

911's advantage is coming out of turns quicker due to rear engine weight & superior rear suspension

[itsnotanova]

Originally Posted by stephen wilson

You went to the trouble of relocating the battery and you still have a spare tire in the trunk ?

It only is about thirty minutes of work to relocate the battery. It's still a street car and the spare comes out at the track