i wouldn't bother battery weight on a street car...at least not in the first place before replacing all kind of stuff with aluminium and carbon
.... i have a light weight in my Porsche 928 but this is a track car on which everything is checked/changed on weight ... you can start cold with a extern battery and the light weight is only for a few starts/ emergency start... on a circuit. On the street you have no help on every corner... those modern light weights have enough amps to start but no much amps/hour... so i'm afraid flooding the engine and you need to cranck a little time could already cause a flat...also on a moment you need voltage from the battery for ignition... the alternator isn't helping yet. I had all kind of brands over the years in my cars , one has to be lucky that it is not a "monday" made battery
Myself had a bad experience with a ( expensive ) Optima, best experiences and now using are Bosch closed cells. But then again, it depends also on daily- 2 times a year ? use, equipment for charging etc...
