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A quick question: The stock battery in my 02 Z finally died and I want to replace it with an Optima. Which is best for a car that is a weekend driver [sits for 4-5 days at a time - red or yellow top] and what specs do I need [650, 750 CCA, etc]? Thanks for your help. Happy New Year.
Quick newbie question. What do the numbers mean. I just got an optima 75/35 battery. But I have no idea what the difference between 75/25 and 75/35 is. Any insight?
Quick newbie question. What do the numbers mean. I just got an optima 75/35 battery. But I have no idea what the difference between 75/25 and 75/35 is. Any insight?
Quick newbie question. What do the numbers mean. I just got an optima 75/35 battery. But I have no idea what the difference between 75/25 and 75/35 is. Any insight?
Good question.
The battery group designation is a universal standard which only refers to physical battery size dimensions. Much like the AA, C, D cell designations of household electronic batteries. Having a standard means you can buy any brand battery inthat group size and know it will fit your application.
The fact 2 numbers are listed on Optimas is because the group 25 battery calls for top posts, the 75 uses side posts. The Optima has both, therefore it fits both group dimensions..
This is just my educated guess....but Optima includes that plastic height spacer which (when used under the battery), makes the group 25 battery fit a group 35 application by making it taller.
Wholly crap, man...how long did it take you to assemble all that?
Nice job.
Btw, I don't know if or where I corrected you. The chart I have that lists battery group dimensions list the same max dimensions for both group 25 and 35. The key word there is max...so i'm still unsure if the height is really the difference or not.
I can find plenty of places selling the 75/35 Optima...but I cannot find that on Optima's website, they only list the 75/25.
The difference could be something recent, and might be a difference in post location too, I'm really not sure yet.
But no matter, I'm confident it is the same battery.
Thanks! I guess it's taken a while to compile the information, but I update a little bit at a time, so it doesn't seem like much. It's a ton of information already, but it's still growing. I may be taking apart my entire front and rear suspension next weekend, or at least in the next month or two, so whenever I do that, that thread will grow substantially.
You corrected me when I said the Optima model numbers didn't mean anything, and you proved that they do. At the very least they make the difference between top or side mounts, even though the Optima has both.
I tend to think the numbers don't matter, but that's because I want a smaller, lighter gel-battery. The posts don't matter to me because I can buy/make adapters. I sometimes fail to remember that certain details that matter little to me may make a world of difference to someone else.