You don't need a big-*** battery, you need a big-***
alternator and appropriately-upgraded charging system wiring to accommodate it.
As for Optima batteries: No, they haven't been worth the price for many years (not since the price went up and the quality went down). Here is what I posted on the subject in May 2008:
Optima used to be the premium battery. When I worked at the wrecking yard in the mid-late '90s, Optimas cost more on the used-battery rack than any other kind. And they were the ones that tended to disappear; if an Optima came in under the hood of a junked car, whoever first saw it would usually grab and stash it. But Optima has been through several corporate "parents". If I remember the sequence correctly, the original manufacturer was Gates (as in belts and hose, in Denver), who originally called the spiral cells in the Optima battery "Gates Cyclon" cells. Then Gates sold the battery operation; somewhere in there a Swedish operation was involved, then somebody else was making them, and quality control went awry. If you got a good one, you were fine, but there were far too many bad ones, and as I understand it (I had quit buying Optimas by then) the multiple sequential brand owners didn't care much about people who'd bought batteries from the previous owner of the brand. I have no up-to-date info on how reliable they are currently; I think Johnson Controls now make the Optimas, and JCI have a good reputation in the field, but I don't consider them cost-effective because they remain considerably more expensive than other batteries without a sturdy track record of being worth the extra money in the long run.
My last few battery replacements have occurred such that a right-now replacement was necessary, limiting my options. I've wanted for some time to go buy a battery from one of those local places that makes them on-site, complete with old-fashioned one-per-cell round filler caps. There were several such places in Eugene OR when I lived there, and I have to imagine there are some here, too. As it stands, my last two batteries have been one spiral cell Optima-type unit made by Exide (their "orbital" design) and branded as Motomaster for Canadian Tire, and one Motomaster Nautilus marine deep-cycle item, both purchased from Canadian tire. One's in the Dart, and one's in the truck, and I don't recall at the moment which is in what. I like the deep-cycle batteries because they're considerably more resillient and tolerant of sustained light-to-moderate load (e.g. leaving the lights on), they have convenient threaded-stud connections near the terminals that make it easy to add electrical accessories, and as long as picked correctly they have much more than enough high-load capacity to start the car very reliably even in very rough (cold or hot) conditions.
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And here's what I wrote on the subject in October 2009:
Yesterday I hopped in Dart III (my new '73) to head grimly to my office and try to grind out the rest of the giant report I've been procrastinating for months. Turned the key and was met with a mighty roar of…silence. F(comma)WT? Ooops…I'd left the lights on the previous morning when I parked. And what's worse, I'd left the
parking lamps on, not the full headlamps. The smaller the electrical load, the more completely the battery drains—this one was well beyond pining for the fjords.
No jumper cables, of course (memo to self: get).
I borrowed a car and drove over to the office, retrieved the fancy Exide Orbital spiral-cell battery yanked from the truck last December before I sold it, drove home, and tossed it in the Dart which started immediately, and the ammeter showed only very brief charge-up before settling down to the middle again. Those
spiral-cell batteries really work a treat — this one held a full charge for nearly a whole year just sitting in a storage locker, which is a neat trick — but I think I will probably install a
daytime running lights module and a lights-on reminder buzzard on Dart III.
Now I'm out West; Dart II ('64 273) is in the driveway and I
still have to finish that stupid report. :roll:
(In case anybody's wondering what a headlights-on reminder buzzard would be like, or how I'd add it to my old Dart: I'd procure a buzzard and set up housekeeping for it in a tree near where I park. If ever it saw me get out of the car without turning off the lights, it'd flap around and squawk for fifteen seconds or so. If I didn't get the message and began walking away from the car with the lights still on, it'd swoop down and probably vomit all over me. And then I'd be like "Oh yeah, right, I left the lights on".
I wouldn't be tempted to take the headlights-on reminder buzzard on plane trips with me, though; they're notorious for overpacking and that just wouldn't work out, not with each passenger being limited to just one carrion item.)
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The Exide spiral-cell battery described above, purchased in 2006 or so, is still in Dart III.