I need a new daily battery...sort of

[audiolife 5,000+ posts]

Total, about 4500.

how much of that is going to your subs?

 

[528hz 10+ year member]

I would love to know how the CA and CCA numbers you give equate to car audio power. Please enlighten us.
Let me give you a little hint... NOTHING!

CA and CCA are measurements of how much amperage a battery can provide for 30 seconds with the battery staying above 7.2v. Do your amps run at 7.2v? I have never seen any that do.

Now let's look at the aH rating. That would give you some indication as to how long you could run your audio system. It is not easy to do an exact measurement of time, but it is a good apples to apples comparison.

So when your stock battery has an 100 aH rating and the Batcap 2000 has a 50 aH rating, the stock battery could play your music for twice as long as one 2000, or the same as two 2000.

Now the aH test is conducted without any charging system (alternator) but the aH rating still applies even when you have a charging system present. If your audio load is a constant 200a draw and your charging system can only provide 160a, then the remaining 40a of current will be provided by your battery.

Now that 40a load will drain one 2000 much faster than the stock battery and we know this because of the aH rating.

CCA also takes into account that the discharge is at 0 degrees too.

How can you say that CCA doesn't apply to car audio? Why aren't there more topics about Ah than CCA?

We're also not talking about a competion car, this is a daily driver, and I don't blast my stereo at all times, so the Ah rating would apply to an hours time, not 30 seconds on my volume on the HU.

I'm not trying to argue with you, but I understand what you're saying.

 

[528hz 10+ year member]

how much of that is going to your subs?

4200.

 

[audiolife 5,000+ posts]

CCA also takes into account that the discharge is at 0 degrees too.
How can you say that CCA doesn't apply to car audio? Why aren't there more topics about Ah than CCA?

We're also not talking about a competion car, this is a daily driver, and I don't blast my stereo at all times, so the Ah rating would apply to an hours time, not 30 seconds on my volume on the HU.

I'm not trying to argue with you, but I understand what you're saying.

I have seen a higher rated CCA flooded cell (golf cart type battery) not be able to start a big old dodge 440 engine while a smaller CCA battery could start it. Both batteries were new and charged from the same charger same setting (one was from a golf cart the other from a scooter). Its where the power is usable to the car. In a more modern fuel injected car you go below 10 volts I doubt you are starting anything, plus it doesn't take 30 seconds to start a modern car. CCA and CA were specs from way way way way back before WW2.

 

[528hz 10+ year member]

Well, I'm off to buy a DieHard and give it a go.

I'll come back to this thread and report if my car is fvcked or not.

 

[audiolife 5,000+ posts]

4200.

I would either get a bigger alt or more batteries unless you watch what you are doing with a voltage gauge and plan on using a charger often unless you are willing to drive around with the tunes turned down often.I have seen guys run 16k watts off a stock alt and 9 g 31 sized batteries and I have seen others burn stuff up fast going smaller. 4500 watts and being that it is a car (less room) I would get as big of an alt as I could.

 

[528hz 10+ year member]

I think I'm going to do that too.

So let's run this scenario:

If I had a 250a alt, 2 Batcap 2000s and my stock battery, do you think that would be sufficient for the 4500?

 

[audiolife 5,000+ posts]

I think I'm going to do that too.
So let's run this scenario:

If I had a 250a alt, 2 Batcap 2000s and my stock battery, do you think that would be sufficient for the 4500?

if you have 3 2000's already use them! I would rather have too much than barely enough. That was kind of my point about the depth of discharge. Only way I see your under the hood battery being and issue is if it is not isolated and doesn't get along with the batcaps or there is something specific your car needs from the battery they put in it to start with which I doubt. I know stuff gets expensive but blowing an amp or killing batteries for no good reason gets more expensive and bothersome for no good reason.

 

[528hz 10+ year member]

if you have 3 2000's already use them! I would rather have too much than barely enough. That was kind of my point about the depth of discharge. Only way I see your under the hood battery being and issue is if it is not isolated and doesn't get along with the batcaps or there is something specific your car needs from the battery they put in it to start with which I doubt. I know stuff gets expensive but blowing an amp or killing batteries for no good reason gets more expensive and bothersome for no good reason.

I hear you sir. And I'm not trying to be cheap by any means.

I'm just not too sure a bigger alt will fit under the hood without major bracketing and modification. I've looked under the hood, and I don't think I have the 2" around the alt. that Mechman requires for a larger casing.

After this whole debate, I'm wondering whether I should just say "fvck it" and keep my amp wired @ 2 ohms. I don't think it would be that big of a difference in audibility from giving them 1000 watts compared to 800 watts each 12".

And yes, that is what this entire issue is about...1000 watts each, or 800 watts each.

It is a sealed box with four 12".

 

[audiolife 5,000+ posts]

To see/hear a diff you have to pretty much double the power. Anything less is nit picking and you must likely would need a meter to tell the diff.

 

[infamous_e46 5,000+ posts]

Yep!
Goddamm Germans! They need to at least put the CCA rating on 'em.

Have you switched yours out?

Yeah mine died while I was running my hifonics samson xi I ended up getting the duralast gold replacement and voltage stays in the high 13's at full tilt with the oem h/k amp and my alphasonik pma1000hca high current a/b class bridged at 4ohm 1575?? watts