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Re: Battery Sizing - am I crazy?
I can't see that wet cells vary from 105 to 130Ah in the same size group. IIRC a G31 was "always" rated around 100Ah ten years ago, and no one has made astonishing breakthroughs in chemistry, meaning they'd have to thin the case walls down to stuff in 30% more plates.
Dunno, Maine, but it smells like someone is using a rubber ruler to get some of those numbers. Have you done any cycle testing to see how those numbers play in the real world? I just can't see a full 1/3 difference in capacity being real.
When Miata was a big new thing, AGM flat plate batteries were almost unheard-of, which may be why Mazda used the Optima. Or, again remembering the time frame, someone could have cut them a loss-leader deal to promote the brand. But Mazda learned a big lesson from Fiat: Wet lead battery in trunk means big time corrosion problems from acid vapors. BMW currently puts wet lead acid in the back of the X3/X5, but of course they found a superior (cough) way to engineer it, with a little breather hose to vent the battery under the car. So it can rot out the underbody instead.
I only got 8 years from my last abused AGM. In which time I think the prices doubled. (Ouch!)
Last edited by hellosailor; 11-27-2012 at 04:47 PM.