BMW Z3-Is this good CCA?

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2000 BMW Z3 2.5 location Dallas Texas
Battery has 650 CCA and 810 at 32F

Battery came from another car and it holds charge at 100%. What I am not sure about on this batt. is if its rated cranking amps are sufficient for this car-because obviously I would rather be above the required CCA. Living in Dallas-our 4 weather seasons are hot, hot, hot & hot. With a couple of days dipping to freezing. We don't use the car in those days-it's a weekender and mostly parked. Looking at this battery's CCA, is this suitable for this car?

Also living in a hot climate which CCA is determine will come into play at cranking the car - the 650CCA or the 810CCA at 32F?
What is the significance of each?



Here is the test from AZ

 
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For BMW, the aH rating is the most important part. Not the CCA. Find out what the factory specified aH rating is for your configuration and make sure the replacement matches this.
 
I just checked. Your application calls for BMW #61212353806 which is a group 48 with a 70aH rating.
 
Originally Posted By: The Critic
For BMW, the aH rating is the most important part. Not the CCA. Find out what the factory specified aH rating is for your configuration and make sure the replacement matches this.


thumbsup2.gif
 
Should be fine for the coming warm season, but i might get an oe or higher before winter. I always get the most CCA avaliable in whatever battery type it is when i replace a battery. I figure why not? If a few extra bucks gets me an extra year of life or keeps it cranking below zero better its worth it to me.
 
I would be much concerned about proper venting of that sub floor trunk mounted battery than CCA. There have been "issues" with using an incorrect battery in that location......... issues like KABOOM!!!! upon start-up. Group 48 is vented - is yours?

BTW - those AZ battery/alternator testers are very marginal at best.
 
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Batteries wear out quicker in hot weather than in cold, so the short duration of cooler weather you experience won't do a lot to slow the reaction rate.

650 is sufficient but as mentioned above 800 would be better - so long as all terminals are clean and tight and all your earthing is good then you should be ok but don't count on OE levels of longevity
 
Originally Posted By: KMJ1992
Should be fine for the coming warm season, but i might get an oe or higher before winter. I always get the most CCA avaliable in whatever battery type it is when i replace a battery. I figure why not? If a few extra bucks gets me an extra year of life or keeps it cranking below zero better its worth it to me.

With really hot weather, having high CCAs can be a compromise depending on how it got there. A larger battery producing more CCAs isn't necessarily bad. If they have thinner and more plates to achieve that, then it's going to be worse. The plates might warp or might not reform as well in high temps.

Few OEM batteries are high CCAs. I remember my Group 51/51R OEM batteries were all rated at 400 CCAs. The replacements I got ranged from 425 to 500 CCAs. I live in a mild climate so I prefer the lower ones for better longevity.
 
Originally Posted By: user52165
I would be much concerned about proper venting of that sub floor trunk mounted battery than CCA. There have been "issues" with using an incorrect battery in that location......... issues like KABOOM!!!! upon start-up. Group 48 is vented - is yours?

BTW - those AZ battery/alternator testers are very marginal at best.


There was a Porsche driver killed recently by an overcharging battery venting to the inside of the car.

http://www.dailymail.co.uk/news/article-...ar-battery.html
 
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I realize that most motorists don't know anything about batteries, other than when they have a dead one the vehicle won't start. But it seems like the smell would have been pretty overpowering inside that Porsche. Wouldn't you roll down the windows or something to vent the odor in a situation like that?

They are kind of quick to blame the battery here, it may be the alternator overcharging that battery.
 
BMW's can be fussy about having the wrong type battery or even slight power variations with the proper one. Between that, the potential venting issues and having the car sitting for extended periods I'd spring for the proper group size. You may have zero issues.
 
Electrically, that battery is fine, more so in the Texas climate.

As mentioned, the OE battery for that car was a Douglas-made Group 48, spec'd at 70AH / 570A EN. BMW tends to favor reserve capacity over cranking amps, so an aftermarket battery like the DLG may not last as long.

Physically, the T5 is slightly smaller in height and length than a 48/H6, so it might have to be shimmed to fit securely, if the BMW cleat clamp isn't able to already accommodate it. (it looks like you've already done a test fit)

That style of JCI case has venting provisions on either end (in the one pictured, one vent opening adjacent to the UPC code is already closed off with the yellow plug), so it's just a matter choosing the right end and fitting the hose/swapping the plug.
 
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Originally Posted By: The Critic
For BMW, the aH rating is the most important part. Not the CCA. Find out what the factory specified aH rating is for your configuration and make sure the replacement matches this.


AH rating is irrelevant unless you're planning to deep-cycle the battery. In which case you should be using a deep-cycle battery, not a starting battery.

For a starting battery, CCA is the correct rating to use.

The only reason BMW specifies an AH rating is because that's how starting batteries are rated in Europe. For whatever reason, the more sensible measure of starting battery performance, the CCA rating, never caught on there.

For a given size, a deep-cycle battery will have a lower CCA and a higher AH rating than a starting battery, which will have a higher CCA rating and a lower AH rating.

Compare the specs on the following batteries and you'll see what I mean:

Group 24 automotive starting battery

Group 24 marine starting battery (has SAE and threaded terminals)

Group 24 marine "dual purpose" starting/deep cycle battery

Group 24 marine deep-cycle battery

CCA is determined by the surface area of the plates. AH is determined by the mass/weight of the plates.

A starting battery uses a more spongy lead that has higher surface area, but comparatively less weight/mass than the more solid lead used in deep-cycle batteries.
 
Originally Posted By: brianl703
CCA is determined by the surface area of the plates. AH is determined by the mass/weight of the plates.

How you get there matters though. A lot of factory-installed batteries have a lower CCA rating than aftermarket batteries of the same size. That's not necessarily a bad thing. If the manufacturer achieves a higher rating by putting in more (but thinner) plates, then that's not going to be that great for someone in Texas where it's going to fail faster in the heat.
 
There were (maybe still are) north/south versions of car batteries. The north version will have higher CCA, whereas the south version will stand up to heat better (maybe with thicker plates so it's more like a deep-cycle than a starting battery).

I've always thought that in a mild climate, a deep-cycle battery might last longer than a starting battery.

I've never tested this because:

(1)I've never had a car that takes a group size available in a deep cycle version

(2)The warranty on deep cycle batteries is only 12 months. Probably because they get abused (left discharged in the boat all winter, etc).
 
Originally Posted By: brianl703
There were (maybe still are) north/south versions of car batteries. The north version will have higher CCA, whereas the south version will stand up to heat better (maybe with thicker plates so it's more like a deep-cycle than a starting battery).

Factory-installed batteries seem to be completely different than anything that can be bought at retail. They seem to be different than even the one sold at the dealer. They typically list the minimum CCA rating specified by the carmaker.

However, it could have something to do with how new cars are treated by dealers. The barely get driven, sit in a lot or garage possibly waiting weeks or months to be driven, and maybe just moved from one spot to another. I suppose having thicker but fewer plates and less CCA helps with that kind of use.
 
Originally Posted By: brianl703
Originally Posted By: The Critic
For BMW, the aH rating is the most important part. Not the CCA. Find out what the factory specified aH rating is for your configuration and make sure the replacement matches this.


AH rating is irrelevant unless you're planning to deep-cycle the battery. In which case you should be using a deep-cycle battery, not a starting battery.

For a starting battery, CCA is the correct rating to use.

The only reason BMW specifies an AH rating is because that's how starting batteries are rated in Europe. For whatever reason, the more sensible measure of starting battery performance, the CCA rating, never caught on there.

For a given size, a deep-cycle battery will have a lower CCA and a higher AH rating than a starting battery, which will have a higher CCA rating and a lower AH rating.

Compare the specs on the following batteries and you'll see what I mean:

Group 24 automotive starting battery

Group 24 marine starting battery (has SAE and threaded terminals)

Group 24 marine "dual purpose" starting/deep cycle battery

Group 24 marine deep-cycle battery

CCA is determined by the surface area of the plates. AH is determined by the mass/weight of the plates.

A starting battery uses a more spongy lead that has higher surface area, but comparatively less weight/mass than the more solid lead used in deep-cycle batteries.


I understand your position. However, the issue with BMW is that the newer models use a "smart" charging system that relies on the aH rating of the battery in order to deliver a proper battery charge. Installing a battery with a different aH rating (or a different type) will often require the car to be re-coded.
 
Originally Posted By: The Critic
Originally Posted By: brianl703
Originally Posted By: The Critic
For BMW, the aH rating is the most important part. Not the CCA. Find out what the factory specified aH rating is for your configuration and make sure the replacement matches this.


AH rating is irrelevant unless you're planning to deep-cycle the battery. In which case you should be using a deep-cycle battery, not a starting battery.

For a starting battery, CCA is the correct rating to use.

The only reason BMW specifies an AH rating is because that's how starting batteries are rated in Europe. For whatever reason, the more sensible measure of starting battery performance, the CCA rating, never caught on there.

For a given size, a deep-cycle battery will have a lower CCA and a higher AH rating than a starting battery, which will have a higher CCA rating and a lower AH rating.

Compare the specs on the following batteries and you'll see what I mean:

Group 24 automotive starting battery

Group 24 marine starting battery (has SAE and threaded terminals)

Group 24 marine "dual purpose" starting/deep cycle battery

Group 24 marine deep-cycle battery

CCA is determined by the surface area of the plates. AH is determined by the mass/weight of the plates.

A starting battery uses a more spongy lead that has higher surface area, but comparatively less weight/mass than the more solid lead used in deep-cycle batteries.


I understand your position. However, the issue with BMW is that the newer models use a "smart" charging system that relies on the aH rating of the battery in order to deliver a proper battery charge. Installing a battery with a different aH rating (or a different type) will often require the car to be re-coded.


Agree. I had to re-code my car when I put a larger size AGM into it..

Much of the battery talks in "c-rate", which is a multiplier of Ah energy capacity to determine current.
 
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