This spring I will be shopping for a new battery for my '68 442 convertible with the 325hp 400. Looking for a good battery that will fit and can hold a charge under extended periods (30 days) of non use of the car. Is an AC Delco battery satisfactory for periodic cruise night and Sunday drives use or is there a better choice out there I should be considering?

Thanks,
Phil

 

Most brand name batteries that fit the pplication will be fine. What kills a battery is starting the car occasionally and then letting the battery sit half charged. The battery needs to be charged first and then stored at top voltage using a battery tender that will keep it there.
Allowing a battery to sit at less than full voltage 12.6 to 13.2 is what kills them. Most people don't realize at 12 volts is basically dead and needs charging.

 

Thanks... I usually keep the battery strength maintained using a tender. I have been hearing some "not so good" things about the AC Delco stuff they offer today so that's why I was wondering if another alternative may be better.

phil

 

As strange as it may sound but Walmart is one of the best places to go. This discussion comes up pretty often on here and this seems to be a well supported opinion. Their price and quality are hard to beat.

 

I've got Delco batteries in all 3 cars - '68 4-4-2 auto, '69 4-4-2 auto, and '71 Corvette auto. The battery for the '69 has been around since 2007 and shows no signs of giving up as of yet. I use battery tenders on all 3 cars and I credit them for keeping the batteries alive and well. I also use a battery tender for my rider lawn mower and it has kept that battery going for 11 years now.

Randy C.

 

my cutlass came w an optima battery i like it because no outgassing or leakage....when it dies i will get another

 

Get a battery that matches up with your stock application (cold cranking amps,etc, etc, etc) all those numbers should be matching with spec range. this info in a manual somewhere.

As far as 30 days + good battery, Any new or good battery should be able to do this task. Ive experience 60 days for shure.

Is it possible you have a parracitic draw? if so, you should find it first before it defaults your new battery.

short term non usage plan could be you buy a 5 dollar battery terminal that lets you manualy cut connection to your battery. Link--------http://www.ebay.com/itm/like/380465824854?lpid=82&chn=ps&ul_noapp=true

And like above, get a good brand.

 

I've wondered about those Optima batteries. Right now I have a Sam's Club battery in my 71 98 but it is overdue to be changed. If I don't end up with one of those Optimas I will probably get another one from Sam's Club.

 

True for our usual conventional wet-cell batteries.

Another thing that kills conventional wet cell lead-acid batteries is rapid charge. If your conventional battery is discharged and you use the alternator to recharge, this reduces life each time.

The solution for wet cell batteries is to drive them regularly or keep a small top-up charger on them when idle.

AGM batteries (the sealed ones that can't spill acid) are much better suited to cars that aren't driven regularly or kept on constant charge. They accept rapid charge without damage and can sit for long periods at partial charge without harm.

They also have higher cranking power for the weight of the battery versus wet-cells.

AGM batteries are available from Optima (as mentioned), Odyssey, Northstar, and others. Restoration Battery in Ohio makes Delco-branded AGM batteries that are look-alikes to the assembly line batteries.

 

Optima are gel-cell technology. The newer AGM (absorbant glass mat) are more powerful, smaller, lighter, and provide excellent performance even when partially charged.


I have a Braille AGM that is about 6 years old now, has sat for over a year at one point, and still works great. I've also used a couple of AGM's from XS Power that have been great. XS Power is now carried by a bunch of high-end stereo shops, as the car audio crowd has discovered how powerful and long lasting they are.


The thing that is VASTLY different with the AGM batteries, is that the CCA (cold cranking amps) rating is NOT a good way to judge and choose these. A 500cca AGM will outperform a 1000cca lead-acid battery.


I've seen "AGM" batteries at the local parts stores, but I'm dubious of those. Summit, Jegs, and stereo shops carry the REAL AGM batteries. I'd stick with XS Power or Braille.

 

Here's a cool website:

http://www.autobatteries.com/en-us

 

Not sure where you guys are getting your AGM information? AGM batteries are MUCH heavier than a led acid. I deal with AGM's on a daily basis and they do have some good applications but you will not see me buying one any time soon. From my extended experience of AGM batteries, they will last longer if the charging system is working good but as soon as you have trouble with the charging system or let the battery go below dead (about 11.5 volts) then the battery will not likely live long after that. Any AGM brand we have used, if it goes below 10 volts it will likely not ever recharge. This included, Exide, Optima, Odyssey and many others.

I am dealing with industrial batteries so maybe something is different in the world of automotive AGM but I would not think so.

 

I wonder if this would happen with one of the deep cycle AGM batteries like the Optima blue top? They're designed to be used like that...

 

Also, Go with the lowest CCA that you need. Don't buy into the traditional thinking of the higher CCA the better. If you do not live in or use it in a cold climate then a lower CCA will last longer than a high one will providing that the lower one is still large enough for the application.

 

The only Optima batteries I have experience with is the yellow top

 

I'm speaking from direct experience. I've been using AGM's in automotive applications for about 8 years now.


The XS Power 925 is the same dimension front-to-back as most regular car batteries. But, side-to-side and top-to-bottom it is about 3" smaller. It weighs about 25 pounds, which is about 20 pounds lighter than an Optima, and at least half the weight of a lead-acid battery that I would have needed for a 2-ton 10-second street car.


Here is a link to the battery I mentioned above: https://www.summitracing.com/int/par...s925/overview/


Most street cars don't even need the power of that battery, and could use one of the smaller versions that weigh less than 20 pounds.

 

I have had good luck with Kirkland brand batteries from Costco. Costco also has very competitive prices on Optima batteries.

 

I don't have the link but I've read where there is only two or three companies actually making wet cell batteries these days, Exide, Johnson Controls & maybe one other. I have an Exide 800 CCA in my car now that I got from BJ's Wholesale Club. It's not in there long enough to form an opinion. Prior to that I had an Optima. I've had three Optimas. The previous two were fine. This one failed prematurely. It was deeply drawn once by a bad alternator. I've read where other people had them fail early as well so you can get good or bad ones just like any other battery. IMO they aren't worth the extra $$.

 

I have 3 Optima's, 2 red and 1 yellow. 1 red has been in the car for 8-9 years, the other 6-7 years, yellow only about 3 years. All 3 are on trickle charger when not driven. No issues whatsoever.

 

I will say this, If the car does not have a drain on the battery, the AGM will keep a holding charge for a couple years without loosing anything. Even without a trickle charger. That is nice. Another thing, it should never leak acid on your core support. As long as the charging system is good and no mistakes are made in 10 years, they should last 10 years easy.

 

x2

 

Just to clarify. Each cell in a 12v battery is fully charged at 2.1v and there are 6 cells. So 6 x 2.1 = 12.6. 12.6v would be a fully charged battery.

 

My Walmart Everstart 2 year battery finally gave out after 9 solid years of service in Oct of 2015. My car is a year round daily driver. I can't believe how much batteries are now a days, $111.00 walk out. There was not much price difference for a 5 year vs 2. So I bought a group 24F 750cca to replace my group 34 that was only 660cca. Both were basically the same physical size. Hopefully it lasts as long as the old one. The Eversart batteries are made by Johnson Controls and I guess are American made.

Here is a battery state of charge chart for both wet cell and AGM corrected by temperature.

 

Cold and sitting kills regular batteries up here, had a few get low and freeze. Also big CCA is necessary for -40 starts , good to know about AGM, I was considering one, forget it. I had some really good luck with Walmart batteries, now no warranty on the deep cycle and I only 3 years out of a 800CCA battery. That seems to be the trend with a lot of batteries these days, short life span.

 

I routinely get 7 to 9 years out of my batteries in Vancouver. I would never push it to 5 years in a Winnipeg. Makes you wonder if a battery blanket might be a good investment.