They do not mention that they make a battery for Porsche. Do you happen to know which model will fit ?

 

+1 The Optima is what I use in our Nautique boat that sits unused in a marina for 7 months, and it starts every spring w/o any supplemental charging. Check w/ Costco, usually runs about $100-$150 depending on application.

 

I have used Optima previously but they are not DIN style case, so a mounting bracket is required or a commercial one can be purchased such as:
http://www.allzim.com/acatalog/Optim...__911_928.html
The model is Red Top model 34 or 34R ( for RHD or LHD need to check)

 

thank you for the follow up, will bookmark page for future needs.

 

This thread is useful:
https://rennlist.com/forums/996-foru...a-battery.html
It is the 34R (reversed terminals) for LHD models, purely because optima batteries are also physically short and the posts will be better placed for cable reach.
Optima batteries have smaller capacities than lead-acid but they have very low internal resistance (due to spiral wound internal plates) allowing high output currents.
For users who for some reason require more capacity drain during non charging periods, the yellow top deep cycle models are available.

 

For interstate battery replacements:

https://rennlist.com/forums/997-foru...ouncement.html