240Z Battery Size

[DougN]

After searching the archives, I was unable to find the info I need. I want to know if anyone can tell me what size battery is closest to the original size battery for the 240Z? Also, if anyone has any recommendations for where to get one (NTB, Sears, PepBoys, etc) and what specific battery they sell that is a match, that would be great as well.

[Arne]

Doug, it's either a Group 24 or 24F, I can't remember which off the top of my head, and I rode the motorcycle to work today and can't look at it. The difference between the two is that the posts are reversed.

And actually, depending on your cables, either might work. I've got the correct one in the red car, and the 'incorrect' in the yellow with the cables rerouted.

But again, the physical size is Group 24/24F.

[CoastGuardZ]

Group 24 is "original" size. 24F has the reversed terminals which I recommend because it puts the negative terminal under the fender instead of the positive - just remember to reroute the cables.

Both batteries can be had from Nissan if that matters to you.

[Carl Beck]

Doug:

I take it that you want the correct battery size - because you are using the OEM battery hold down on top of it. (yes/no?)

If that is the case - then take the OEM Battery hold down (that sits on top the battery) with you when you shop for a battery. Todays "Group 24" may or may not be the exact identical size as they were in the 1970's... Secondly many battery manufacturers have moved the original position of the battery terminal posts - so they now sit closer to the middle of the battery (for a more "universal" fit and broader application). This can be a problem with the OEM battery cables - as they can come into contact with the metal battery hold down.

If you look at the OEM battery hold down - that sits on top the battery - you will see that it is "notched" out where the battery terminal posts are originally - so that the battery cable terminal will not come into contact with the metal frame...

Additionally - the battery terminal Posts are today a slightly different size than they used to be. The difference in size between the + and - posts have also been changed. Sometimes the old Cable Terminals will not tighten down correctly on the newer design battery terminal posts...

The last time I looked - Interstate built the only Group 24 that still was a "close fit".. but it wasn't perfect. I've switched to using the Optima's... they don't fit perfectly either, but they don't leak battery acid down on your frame rails either...

FWIW,

Carl B.

[DeesZ]

I looked at batteries very recently until I passed out. In agreement with everyone else, "Group 24" is what you want if you wish to stay close to OEM, and check your cables and post placement to decide on the issue of 24 or 24F. The following is my opinion and to be considered for what it's worth.... The only downside to the positive post facing the engine is that I could screw up with a wrench, etc. and there it will be to do me in. (I already have a few blue tinted wrenches from past escapades.)- maybe that is Nissan didn't put it there in the first place - I don't know for sure. I did not like the positive under the fender metal, but the hold down system is adequate to prevent disaster - I added a plastic/rubber 'cover' for the terminal, but ended up discarding it and am now comfortable with the placement and hold-down system.

There is a full range of batteries out there with respect to quality, construction, warranty, and cost. There are also only about three companies who manufacture the bulk of them... Johnson Controls, Exide, and another I can't recall at the moment. I almost went with an Optima or the NAPA equivalent (O-9, or something like that). I dropped back ten yards after speaking to a few people in the business that I trust. They suggested that the key is getting a battery with adequate Cranking Amps (CA) & Cold Cranking Amps (CCA) and a GOOD warranty, and unless you have special needs or demands, don't let much else fog your decision. CA & CCA needs can vary depending upon where you live. I'm in the NE, so higher CCA was a consideration for me. A "good" warranty to me is defined as the period during which you can get a full replacement for it if it fails. I wouldn't pay too much attention to the number of pro-rated months offered because you won't get much credit. I was surprised by how few batteries come with a three-year full replacement warranty! Once reason set in for me (and it will be different for different people), and I considered 'value' (which to me was cost, available money, other wants, real needs/function for what I am buying, etc.), I ended up buying an EverStart Maxx from Walmart - 875 CA / 700 CCA - 3 year full replacement warranty; cost was around $65.00. Their 'number' is "24N". It fits very well in the OEM hold-down brackets, the posts are forward, with the negative post on the inside, putting the positive in the 'notch' that Carl referenced.

This is also a great time to consider new battery cables. That replacement cost me about $20.00, I did that about a year ago (with the old battery) and that alone made a world of difference. Got them from NAPA and am happy with them as they came with wires fitted permanently on each terminal; the negative wire extends to the grounding point on the firewall without any problem, and the positive is there if you will be using any accessories that need a good connection at the battery. Sorry this got long winded, but it is something that I think is worth factoring in on such decisions.

[hd240z]

The group 24 batteries are be the best "fit" for the original hold down, but I use a group 26 battery since it is smaller and 8 lbs lighter. I still use the original hold down as it has enough vertical adjustment to work with the smaller battery. The positive terminal notch can be positioned in the same location as a 24 battery. You end up having a 2 inch gap on the other end of the hold down, but I have never had problem with it moving even during an autocross. I also pull the battery out of the car every time it goes into storage so lugging it around is a consideration in my case.

[DougN]

Thanks for all the info guys!

[ZIII]

If you're looking for a great battery, consider the Optima.... Have it in all my cars; fits the Z perfect and never do I worry about any possible leaks....

[icehound]

ZIII, is that a group 34 battery?

Dave

If you're looking for a great battery, consider the Optima.... Have it in all my cars; fits the Z perfect and never do I worry about any possible leaks....

[ZIII]

Dave,

Yes it is.... Still have the same battery in the Z, going strong.... You will have to construct a modified tie-down in order to secure it.. The picture above should give you a general idea....

Edited June 23, 2010 by ZIII