Battery and Alternator question

Magicarcher · Post by **Magicarcher** » Sat Jul 22, 2017 7:53 am

My Z has been fitted with an aftermarket battery which is not the best physical fit. From what I can see there are a range of batteries and alternator pairs available for Zs depending upon feature content.

How can I determine the correct CSC and capacity of my battery? So I can check if it ok, because I have had some ECU undervoltage failures.

How can I determine the alternator size on my Z?

Smartbear · Post by **Smartbear** » Sat Jul 22, 2017 8:12 am

Hi, as far as I'm aware the battery doesn't differ according to options? I think the eurocarparts site gives a range of suitable batteries if you enter your reg number.
Are you changing the alternator as well?
Rob

Magicarcher · Post by **Magicarcher** » Sat Jul 22, 2017 8:37 am

I have read somewhere but I can't remember where that there are three alternator/battery combinations. Hence the question.

Magicarcher · Post by **Magicarcher** » Sat Jul 22, 2017 9:19 am

Looks like this has opened a can of worms. I usually use Tayna for my batteries. They recommend only one battery (unusual for them):

Exide Premium EA1000: 100Ah, 900A (353mm x 175mm x 190mm) I am far from convinced that a 353mm long battery will fit within the tray clamps!

Eurocar parts recommend scores, but taking Exide they recommend:

Exide EB620: 62AH, 540A (246mm x 175mm x 190)
Exide EA640: 64AH, 640A (246mm x 175mm x 190)
Exide EA740: 74AH, 680A (278mm x 175mm x 190)
Exide EA770: 77AH, 760A (278mm x 175mm x 190)

BMW (Real OEM) list 3:

01 Original BMW battery (Warranty only) 70AH 1 61218381730
01 Original BMW battery (Warranty only) 55AH 1 61218377139
01 Original BMW battery (Warranty only) 80AH 1 61217604816 640A CC

My car is fitted with Exide EB712: 71AH 670A (278mm x 175mm x 190)

It is as clear as mud!

Ewazix · Post by **Ewazix** » Sat Jul 22, 2017 10:19 am

Its easy to overthink all this TBH most well known brands like Exide or Bosche/Varta made them in a hand-full of factories with different brands & prices, the main differences being the warranty and support.

ECP have batteries including the Exide range with 30% off this weekend e.g. 67cca 100 (71Ah) 3 Year Guarantee - W096SE down from £121 to £81. You have to watch ECP though their deals are often matched or bettered elsewhere including by Tania or ECP's own subsidiary carpartsforless.com

Magicarcher · Post by **Magicarcher** » Sat Jul 22, 2017 12:31 pm

For info ECPs web prices even when heavily discounted are often beaten by their own ebay store, often by quite a margin.

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