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MG MGB Technical - What size/brand for 6volt batteries.

I understand the practability of the 12v conversion, but we (me and my dad) would like to keep it original in any way we can. Can anyone give me the size of the 6volts needed, a good company thats still producing them, and where I can buy them in the US? Thanks!

Bryan Corey

Bryan: Check the Moss catalog for "as original" Lucas 6V batteries. Then order, using the same part numbers, from the Little British Car Company. Much cheaper.
Andrew Blackley

In the US the group number is 17HF. Interstate still makes them. Be prepared to pay $75 each, maybe more. Interstate is a popular company and you should be able to find a dealer easily, but expect to order in the batteries.
Ken Thompson

Bryan. I well understand the quest for "originality" and, in most cases, support it. But, unless your car is a show car, go to a single twelve volt battery. I have, over the last 35 years, used both systems. Now, even my 68GT has a single 12V battery. Only one to buy (about every three years here in Arizona, regardless of the length of the "guarntee") and much less hassle. The Brit battery technology lagged behind the US technology. Thus, they used two six volt batteries long after the US had switched to a single, 12V battery. The quality of batteries today is much better than when I was young. Today, the 12V battery is a better battery than the 6V one because everyone quit using the 6V system years ago. The only reason someone would use two 6V batteries today is that they are running a show car. If that is the case, "shame on you". Les
Les Bengtson

I agree Les... problem is my dad is still calling the shots as Im in his house... and when I get the car for my own with my family and such after college, I will switch over, but in the meantime, he really doesnt want me to.
Bryan Corey

To quote Les “The Brit battery technology lagged behind the US technology.”

Sorry Les but your mistaken, you see the B was about the only U.K. produced car to use 6volt batteries. The M.G. used two 6-volt batteries to help weight balance. You see back in the 60’s, when the B was first produced, 12-volt batteries were quite large and cumbersome so I can believe this is true.
Ian Holliday

To quote Ian: "The M.G. used two 6-volt batteries to help weight balance."

Ian, you may be right, but I hope not. I'd hate to think the MG engineers weren't any brighter than that. If they were counting on the batteries to balance the weight, then they would have to have been counting on the drivers to always carry a passenger of equal weight. Not very likely, since MGs were originally intended to be driven in sporting events where there would only be the drivers, as well as on the street with a passenger. If they were realy concerned with weight balance, then they should have followed Triumphs lead and placed the battery in the center of the car, where it would always balance, skinny passenger/fat driver, skinny driver/fat passenger, or no passenger at all. Failing that, it should have been placed on the passenger side to offset the driver's weight in competitive events.

I don't know why they chose to use two boxes for the 12 volt battery instead of using just one box, but it would be interesting to find out.
Dan Masters

It is true, I read it on some official site one time, or out of the manual, or something. They used twin 6v batteries to keep the weight as even as they could, all the way down to small things like batteries.
Bryan Corey

Bryan-
As has already been mentioned, Moss motors carries the ancient British Lucas tar-top batteries for those who want to keep their cars as original as possible. They're Part# 459-410, and the price is $99.95 each, plus shipping. Of course, as Les pointed out, these are old-technology batteries, straight out of Ye Olden Dayes when British electrical systems were a laughing stock here in the USA. They have a small storage capacity and perform very poorly when the weather turns cold, plus they can be easily drained down to nothing if you keep cranking the engine on a winter's day, so master the use of the choke early, before the weather gets really bad. Originality comes at a price that's more than monetary. If your Dear Old Dad is willing to pay the cost of them, well, let's face it, it's his money, and you're getting them for free, right? Console yourself with that idea as you drive around campus with the Co-Ed of your choice (Restored MGBs are great Chick Magnets). Don't forget to fill the fuel tank with High Octane and top the batteries up with distilled water only.
Steve S.

Ian. I agree with you that this is the most commonly given reason for using the two 6 volt batteries. But, I believe that it is merely a hold over from many years ago when the 12V battery was twice the size of a 6 volt battery and,hence rather big and bulky. By the time the MGB made it appearance, the 12V technology was making some very significant improvements in both internal design and external packaging, resulting in a much smaller and lighter 12V battery than had been availble even a few years before. It is worth noting that the A-H Sprite, used a single 12V battery in their original design and this location was continued after the re-design in 61 and the introduction of the badge-engineered midget. Certainly if the true reason for the use of twin 6V batteries is only for weight distribution, the less powerful Sprite/Midget would have used that system. It is also interesting to note that one of the major steps in preparing most of the race and rally cars was to replace the twin six volt batteries with a single 12V battery. The "official" theory that the twin 6 V batteries were for balance is, to me, a myth. The first time you get into the car to drive it, the car becomes unbalanced by far more than the slight extra weight of a 12v rather than a 6V battery. In fact, the more common, general usage of these cars is a male driver and a female or child passanger. Hence, as a "balance" measure, it would make more sense to use a single 12V battery on the passanger side rather than twin sixes. Hence, my belief that the real reason for the twin sixes had to be either some superiority in battery design or simply "that's the way we have always done it, guv". Nothing else makes sense. Les
Les Bengtson

Dan. Missed your post when I was cycling through. I agree with you, but, since I did not mention it in my other post, hope to mention it now. I have studied "myths" in several fields--things that happen and no one really understands why, hence a "myth" grows up about it and everyone begins to believe the myth is truth. Often, I find they are not, but people keep spouting them over and over until they are difficult to challenge. Les
Les Bengtson

Thanks to all of you replying to my post about using two 6-volt batteries.
Sorry to Bryan to high jacking his thread.
I agree that the weight distributing excuse for the use of the batteries seems far-fetched, but remember we are talking about some 40 plus years ago when the B was on the drawing board. A single 12-volt battery would have been too large to place in a cradle as per the twin 6-volt batteries. I don’t feel that the engine bay could have been considered either, because there is too little room for any sort of battery. I think that the placing of the batteries was an inspired one, it uses up space that otherwise would have been wasted. Les I can't agree with your theory that it is down to “simply "that's the way we have always done it, guv".” After all M.G. (including BMC) had produced several cars with a single 12-volt years before. (I am thinking of the Y and TD and more). I think this “tradition” started with the A and ended with the B! (Via C’s).
May the real reason has been lost in the mists of time.
Ian Holliday

This thread was discussed between 01/06/2002 and 03/06/2002

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