boqueron

I have done part of my home work and made a search. It seems that the a possible choice of LIGHTWEIGHT BATTERIES could be:

Odissey 680
Braille B14115
Genesis G16
Odissey 925 (Heavier, more capacity)


Aparently, it's one of the cheapest ways of saving weight... I suspect that it should have some trade off...

I track my GT3 once or twice a month , I could probably take it ( if needed) once a week for a short 10 miles ride to and from my club, and, at my garage there is no possiblity of having it connected to a battery charger...

Any known issue with this mod ? Is there a basic - and easy- maintenance in order to avoid problems... ?

Thanks to you all for your help....Once again !

2002M3Drew

It's funny, I just spent the afternoon tinkering with my battery (dead) in my older 911. I had been planning to upgrade to a lightweight battery like those you listed.

The funny part is that all along I had been telling myself that my old Delco battery (huge) must be 50-60 lbs, so all of my planning started from that point. The funny thing is that, when I removed the old heavy battery and weighed it, I discovered that it only weighs 38 lbs. It looks like this battery has been in the car for more than 10 years!! So, an Optima would be a straight trade, an Odessey 925 would be a savings of 15 lbs lbs, the braille (the one I would buy...not the 11 lb unit) would be 23 lbs or so. I'm rethinking if that little a weight savings is worth the downside of a tiny battery...

RayGT3

I've been using an Odessey for going on 3 years and have yet to see a down side. I store my car over very cold winters with just a floating trickle charger on it and have had zero problems. Actually these batteries hold a charge better in cooler temps. Even comes with a 10 year guarantee. When not in storage I treat it like any other battery, just lighter. I really don't think you would have any problem letting your car set for a month. I can say one thing this would out perform a lead acid battery hands down.

Mr Michael B

Oh ray. Nice relocation effort there. Farther forward, and lower. Win-win.

boqueron

Thanks Ray,

Is this an Odissey 924 ? If so, why didn't you buy the, lighter, 680 ?

smlporsche

Just got the Odessey for the 944 S2R and it weighs 14#'s so it should be a significant weight reduction.

I just saw on the 944 Rennlist Forum a post on an article that said that the Odessey is really a rebadged battery of another (cheaper ) brand. At the price posted you could easily afford to get 2 !

Here's the link:

http://www.stealth316.com/2-dynabatt.htm

K964

I have the Odessey 680 for my Cup---make sure to connect it to a "Battery Tender" or similar type of charge maintainer if you do not drive the car on a regular basis.
Mike

RayGT3

boqueron
The reason I went with the 925 is at the time there was little experience available with these batteries. So I chose to error on the concertave side to avoid any problems that might have occured. At this point having this experience, I probablly would go with the 680. If I remember correctly the price of the 925 was about $90. the smaller one should be less expensive.

Ed Newman

I ran a Odessey 680 in my car last year and if I did not keep a tender on it, it would not start the car. Too much effort. I am switching to a larger battery this year.

karlooz

how many days did you go between start ups? keeping it on a tender is fine for me, if leaving the car undriven for a few days, but if you need to keep it on a tender between sessions then that IS too much effort. if you can leave it for a day or two without the tender then i just might do the small battery.

thx

boqueron

Ups ! Good info... I do not have an electric plug in this garage...

Does the battery drain even if it is disconnected - with a switch - from the car ?

RayGT3

These batteries hold a charge very well with no load. I think I remember the specs claimed the battery will hold 80% of full charge at something like 60 deg. after 3 years of sitting on the shelf.

It's possible I made the right choice for a street car with the 925 based on the comments here. During the driving season I never use a charger of any sort. In stretches of bad weather it might set for a week or more with no ill effects.

viperbob

925 makes life a lot easier....

Ed Newman

I would leave it for a week or two. The 680 barely starts the car fully charged. The 925 is much more appropriate.

boqueron

Thanks to you all !