Do I Really need a CAP ???

[silvercookie 5,000+ posts]

how old is the battery?

 

[lilmaniac2 5,000+ posts]

just get an optima yellow top is wat they are saying.

No, Im saying do the big three, if that doesnt solve the problem add a second battery. Also The optima YT is not the end all battery, I would rather have a kinetik or a powermaster battery, but thats just me

i think they pretty much said i don need one.
and if i don need one -- theres no need to spen $150 on that optima yellow battery.

guess ill have to try that big 3 thing--seems to be cheaper.

Correct //content.invisioncic.com/y282845/emoticons/smile.gif.1ebc41e1811405b213edfc4622c41e27.gif

 

[lilmaniac2 5,000+ posts]

how old is it?

Do you not read posts before you reply?

 

[silvercookie 5,000+ posts]

he said how old his car was not how old the battery was im askin how old the battery is

my bad i forgot to put battery

 

[lilmaniac2 5,000+ posts]

he said how old his car was not how old the battery was im askin how old the battery is
my bad i forgot to put battery

So his 1996 model Mustang is 1 year old?

 

[lilmaniac2 5,000+ posts]

Vehicle: 1996 Mustang
Also any suggestion which sub to go with?

Car is 96 Mustang Coupe.
Battery, like 1 year old. not sure the kind but i remeber i got it from O'Reilly auto parts for like 70-80 bucks.

he said how old his car was not how old the battery was im askin how old the battery is
my bad i forgot to put battery

both of those were posted before your 2nd time asking how old his battery was

 

[2Tone 10+ year member]

Because you wouldn't need one even if your amp was over a kW.

you need 1 farad cap for every 700 - 1000 watts...

 

[lilmaniac2 5,000+ posts]

you need 1 farad cap for every 700 - 1000 watts...

wrong, read my above posts and you will see why a capacitor is not needed

 

[2Tone 10+ year member]

wrong, read my above posts and you will see why a capacitor is not needed

yeah ok... wouldnt hurt to have 1 in any system... not gettin tech on ya, just do it... lets strain the charging system with as much bull as we can and then ask questions what we should of done in the first place... then you can ad, upgrade , or do what ever whenever you want to... do it... and yes , with every 700 - 1000 watts you should ad a cap... cant stand knowitalls

 

[2Tone 10+ year member]

and and extra battery wont do nothing sense they maintain 12 volts together... it wont do anything unless you ad a isolator to separate them... wont hurt the charging at all this way and you can run whatever you want

 

[slickdaddy 10+ year member]

it's cold, you may need a cap for your head

 

[helotaxi 5,000+ posts]

yeah ok... wouldnt hurt to have 1 in any system ... do it... and yes , with every 700 - 1000 watts you should ad a cap...

I will get all tech on you then. It seems you still have the old mindset that was brought about by the old school idea of what a cap does. It was a decent idea it's just there just wasn't any real physics behind it.

What does a cap do? It stores power. Nothing more. Unlike a battery that stores it in chemical form, the cap stores it as a differential charge between to conductor plates. In theory, this should be easy to tap. In reality, the effective series resistance (ESR) of the cap keeps this power from coming out freely. The cap only charges to the highest voltage in the system. If the car is off, the cap is totally useless since the battery is the highest voltage and stores much more power than the cap and will maintain voltage better than a cap ever could.

With the car running, the cap charges to the voltage of the alt. Let's give the alt some credit and say it runs at 14.4v. Your battery sits at 12.6v with the car off but it also charges to the voltage of the alt with the car running, and until you put some load on it and draw off the skin charge, it will discharge at that voltage, too. SO knowing all that, where does the cap do anything? In theory, it would begin to discharge as soon as the alt capacity was exceeded and would discharge down to the voltage of the battery. How much power could it provide in that gap? I showed the math in a previous thread and the basic result was the theoretical usable power stored in a cap between 14.4v and 12.6v was on the order of 0.5 amp-seconds/Farad. So if you asked 10A of a 1F cap it would give you power for a whole 0.05 seconds before the battery took over. The whole time that it is giving that power the voltage of the system is dropping as well.

Now let's toss in the reality of that ESR mentioned above. I don't have the article in front of me, but Richard Clark (the guy who put the first cap bank in a car remember) ran some numbers with a low ESR cap that basically showed that once you get above a certain amp draw on the cap (I don't remember what the number was, but it was very low) the cap can't provide any power because the difference between the alt voltage and the battery voltage was lost to the ESR of the cap. Now you go from what is, in theory, very little help to what is, in reality, zero help.

So why did Richard Clark put those caps in the car? Simple answer: noise filter. The whole point of that capacitor bank is in the Grand National was to totally filter out the alt ripple from the amp power supply. Nothing more. As a noise filter, a cap works great, it doesn't need to really provide any current to speak of, just do some very minor voltage stabilization. The marketing departments took the "voltage stabilization" statement and turned it into a catchphrase and then extrapolated it to mean helping the charging system. Something that it just can't do.

cant stand knowitalls

Better than know-nothings though don't you think?

 

[shortyg83 10+ year member]

and and extra battery wont do nothing sense they maintain 12 volts together... it wont do anything unless you ad a isolator to separate them... wont hurt the charging at all this way and you can run whatever you want

Shhhhh you just got pwned

 

[2Tone 10+ year member]

I will get all tech on you then. It seems you still have the old mindset that was brought about by the old school idea of what a cap does. It was a decent idea it's just there just wasn't any real physics behind it.
What does a cap do? It stores power. Nothing more. Unlike a battery that stores it in chemical form, the cap stores it as a differential charge between to conductor plates. In theory, this should be easy to tap. In reality, the effective series resistance (ESR) of the cap keeps this power from coming out freely. The cap only charges to the highest voltage in the system. If the car is off, the cap is totally useless since the battery is the highest voltage and stores much more power than the cap and will maintain voltage better than a cap ever could.

With the car running, the cap charges to the voltage of the alt. Let's give the alt some credit and say it runs at 14.4v. Your battery sits at 12.6v with the car off but it also charges to the voltage of the alt with the car running, and until you put some load on it and draw off the skin charge, it will discharge at that voltage, too. SO knowing all that, where does the cap do anything? In theory, it would begin to discharge as soon as the alt capacity was exceeded and would discharge down to the voltage of the battery. How much power could it provide in that gap? I showed the math in a previous thread and the basic result was the theoretical usable power stored in a cap between 14.4v and 12.6v was on the order of 0.5 amp-seconds/Farad. So if you asked 10A of a 1F cap it would give you power for a whole 0.05 seconds before the battery took over. The whole time that it is giving that power the voltage of the system is dropping as well.

Now let's toss in the reality of that ESR mentioned above. I don't have the article in front of me, but Richard Clark (the guy who put the first cap bank in a car remember) ran some numbers with a low ESR cap that basically showed that once you get above a certain amp draw on the cap (I don't remember what the number was, but it was very low) the cap can't provide any power because the difference between the alt voltage and the battery voltage was lost to the ESR of the cap. Now you go from what is, in theory, very little help to what is, in reality, zero help.

So why did Richard Clark put those caps in the car? Simple answer: noise filter. The whole point of that capacitor bank is in the Grand National was to totally filter out the alt ripple from the amp power supply. Nothing more. As a noise filter, a cap works great, it doesn't need to really provide any current to speak of, just do some very minor voltage stabilization. The marketing departments took the "voltage stabilization" statement and turned it into a catchphrase and then extrapolated it to mean helping the charging system. Something that it just can't do.

Better than know-nothings though don't you think?

thanks for clearing that up for me... you have to have no life to be on here everyday, ... i think you read to many magazines and you probably touch yourself over popular mechanics...

 

[helotaxi 5,000+ posts]

thanks for clearing that up for me... you have to have no life to be on here everyday, ... i think you read to many magazines and you probably touch yourself over popular mechanics...

Coming from you that means a lot...//content.invisioncic.com/y282845/emoticons/rolleyes.gif.c1fef805e9d1464d377451cd5bc18bfb.gif You've been on here pretty regularly over the last few days, what's your excuse?