Battery Spec

[_Nathan_]

Anyone know the OEM battery spec or can point me in the right direction, looking at lightweight alternatives and want to know which to get!

Also, anyone know the weight of the standard one?

[shimmy]

OEM mini battery is 55Ah 480cca
185h x 175w x 240l
7.28" x 6.89" x 9.45"

B61.21.8.377.139

[sailorbaz]

I actually just changed mine yesterday, went for OEM and have the old one lying in the garage. If I remember, I'll weigh it later on this afternoon for ya. It's a heavy yoke, but when I looked at my mates 80Ah one in his M3, she's tiny compared to that bad boy.

[Roland]

Just got myself a OEM, too.

Looking forward to get a lightweight from BMW, like Porsche developed.
Just a little expensive!! 2'k

[alexk]

I need to buy one as well...

[_Nathan_]

Cheers.

Re, the Porsche one, you can already buy them:

http://voltphreaks.com/

Work out the cost per KG saved over a red top

[phat///M3]

Originally Posted by Roland

Just got myself a OEM, too.

Looking forward to get a lightweight from BMW, like Porsche developed.
Just a little expensive!! 2'k

How much does that weigh?

[alexk]

I had in my list this battery -> http://braillebattery.com/

This for example is 6 kilos lighter and 31AH... http://www.braillebattery.com/index....teries/b3121c/

[_Nathan_]

Good work. Braile one that might be the ticket is 7.7KG or 1.8KG lighter than similar red top for not much more, thanks.

[shimmy]

found this old m3forum post nathan


First off Exide makes the batteries for BMW (they are the OEM supplier). Schucks/O Reilly/Checker/Kragen/Murray's Auto (all the same company just a different name depending on where you live) sells the OEM exide battery.

http://shop.oreillyauto.com/ProductD...e=5005&PTSet=A

Take off the Autolite sticker and add the BMW sticker and presto you have an OEM BMW battery at $155 vs your dealer price.

There are also cheaper options. The Autozone 49-dl fits and is equivalent to the OEM at $90. Their computer says it does not fit but many have put one in without fitment issues.

http://www.autozone.com/R,53334/init...ductDetail.htm

If you want to go light weight then there is the Mini battery which is the same battery that comes in the CSL. The 47-dl is the mini battery at Autozone for $90. It is only 29.5 lbs so you are going to save 19 lbs over OEM M3 (about 48.5 lbs) going with this option. The OEM Mini/CSL batt is 34.5 lbs and costs twice as much. If you have a large amount of aftermarket electrical gizmos on your car or like to listen to your stereo or run your headlights when the car is turned off then I would stay away. If your car is stock as far as electronics then you can run this without any problems. They are rated for slightly less cranking amps and reserve.

http://www.autozone.com/R,23190/init...ductDetail.htm


There is also the Optima red top #35. It fits with the use of a custom spacer under the hold down bracket. A hockey puck is the most common spacer used. They weigh in at 32 lbs but have the same CCA ratings as the full size battery. The only drawbacks are they are expensive at about $190 and if they run low on juice they quickly become pieces of junk. So if you run your battery down on occasion you need to look elsewhere.

The Optima Yellow top is more reliable and is 36.4 lbs but costs about $220.

Then there is the Odyssey, Hawker, and Braille batteries. These are super lightweight dry cell batteries and are expensive. They will work in a car that has no electronic options on it. They are mostly for track use. If you are a super weight shaving modder then they are the way to go and you can get a 15lb battery to work. As a daily driver I would not recommend them though.