Unkle

On my restored Mk1 golf I had one, but not on the 964 as my car came with a new one. I have a good trickle charger anyway as mine sits all week and longer without being driven, however the Bosch is a 4 year battery i understand so just keep the receipt and save the money!

Banner make good batteries too, but the Bosch should be fine.

http://www.bannerbatterien.com/banner/home/index_en.php

reed

I put a Deka AGM in my car. It's a standard group 48 battery size which means it fits into the factory bracket and looks stock. I bought it over a standard Interstate or Diehard because I just like the piece of mind of a "dry" battery. The price was reasonable at around $140. The model number is 9AGM48.

Unkle

If you want a very lightweight battery and intend to put the car on charge when not in use, and perhaps don't have aircon and audio amps etc. you could try this

Works on the 911 3.0 sc starts first time (according to drivers on a motopsort forum I use)

http://www.braillebattery.co.uk/

2002M3Drew

As a follow-up to my post last Spring about Deka batteries vs. Braille, take not that THEY ARE NOT THE SAME BATTERIES, much to my chagrin! The cases, terminals, etc are all the same, but they are different animals. I had a Braille 3121 in my 911SC without a trickle charger for the better part of three seasons with absolutely no issues. It lives up to its ratings. The Deka versions, however, do not last at all. I put new Dekas in my Miata, 911SC and 964 last spring, and have had nothing but problems in all three cars. They go dead in literally a couple of weeks. So, for lightweight stuff, it's back to Braille!

TR6

I recently had the Interstate MTP-91 go dead in my BMW M Coupe after less than 3 years. Had a hell of a time finding a local dealer to honor the exchange. Interstate signs are everywhere, every Mom and Pop shop is an interstate dealer, and everyone was willing to test it and tell me it was bad. But only one dealer was willing to hand me a new battery. And that guy told me the interestates aren't what they used to be and he hates carrying them because of all the returns. So where does this leave us? For those of us willing to pay $150+ for a battery, why can't we find one that works reliably for 5+ years.

PS. I have an Optima Redtop in my 964. It goes flat once in a while from non use, but so far (knock on wood), it has charged back up. And I haven't done anything special while charging it (because I didn't know any better!).

campoj2

Where does the Sears Die Hard stand? As far as I know if one of those batteries dies you can take it to any local Sears store and they will give you a new one.