OK.... I went to the Optima web page and other pages inside--->
http://www.optimabatteries.com/publish/optima/americas0/en/config/product_info/automotive/starter/technical_specs.html
It seems that the 75/25 is:
- 9.3" Long
- 6.8" wide
- 7.6" High
- weighs ~ 33 lbs.
In contrast, the 34/78:
- 10" long
- 6.8" wide
- 7.8" high
- weighs ~ 38 lbs.
On the one hand...you probably don't need the "bigger" unit ( although fairly equal in size)...due to apparent warm conditions where you live. But the size and weight differences are so small..why not get the "normal" , conventional 34/78 Optima that seems to be standard fitment for our 911's?. I don't think you're talking a racing or super-lightweight conversion..are you?
- Wil
EDIT- by contrast, the 49/93 "big honker" stock battery was ( IIRC) about 2" longer and weighed-in at closer to 50 lbs or so.