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Optima battery

David67

Active Member
So I'm tired of my stupid AutoZone battery and I'm looking buying a optima battery.

I'm going to buy a red top and they offer 2 different sizes the 34/78 or 34R. Which one for my 67?

Thanks
 
I had a 34/78 from 2002 till last year (same battery) until I switched to a lightweight race battery. Worked great. Has top and side posts.
 
Yes, the 34R puts the positive terminal next to the solenoid. That's the one I have in my '67. You could turn the 34 around and the terminals will be closer to the fenderwell. Personal preference, maybe?
 
Oh, and I've had my Optima for many years now and it's never failed to start my car after sitting for many months. And that's a lot of cranking to get fuel back up to the carb.
 
For those of you with AGM batteries like the Optima, get the Optima brand charger! I had two OLD Optimas that had been in my barn for years and a conventional charger wouldn't charge them. I picked up the little $100 Optima charger and it brought both of them back to life in 48 hours and both are now in service in vehicles with no issues. They work very well on conventional batteries too. I love when a product actually lives up to the advertising hype!
 
Strange . I've been using a regular charger for years on my yellow top with no problem. I had a red top in the Fiero and it was dead. Checked the purchase date and still had 2 days left on the warranty. Took it in and switched out with a brand new one...free.
 
Just a little note about AGM batteries. You can indeed use conventional chargers on them....with a caveat. If the voltage drops below a certain level (I think it was 9v but please don't hold me to that), then a regular charger refuses to work. IIRC it's because the circuitry in it won't detect below a certain voltage. An AGM specific charger will detect and charge when the battery is at low levels.

All is not lost though and there's no need to replace that AGM that "won't charge". You can fool a regular charger into charging them. Using a set of jumper cables connect the AGM battery to another battery (AGM OR a lead/acid battery with a good charge). Next, connect your charger to the AGM and charge away. The charger is actually sensing the higher voltage level of the other battery and will begin charging.

I'm not the one that figured this out. I've found several articles from reliable sources on the internet. I shared this info with my brother who has AGM's in his ATV's. He knows a guy that works for one of the battery companies. During a discussion of AGM batteries he asked about what I had told him. The guy asked him where he got his info and when he replied it came from me, the guy told him, "Tell your brother you keep that to himself. He'll cost me money!". I guess the battery industry makes a pretty good profit from replacing AGM's that don't really need replacement!
 
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