ok so i am running a kenwood 180 watt amp not sure what rms altho it has a 25A fuse. also i am running a coustic 180 watt 125watt rms with a 20A fuse. also i am runing two coustic 380 watt 250watt rms power for each and they each have a 30A fuse. now i am runing 4 awg power to a stinger distrib block and i am unsure what fuses i need for each line. but i am wonderng if i will need a cap due to i can get ahold of one its a 1 farad lightening audio for cheap do i really need one?

 

Simple answer, NO. Upgrade the big 3. If you still have problems deal with them. Caps are a band aids, nothing more.

 

yes sir!!

caps are useless...upgrade the big three then you should be fine but beyond that id upgrade your alt

 

ya , the most important thig to upgrade would be the alt. becuz if ur alt isnt replenishing the battery fast enuff you will get dimming lights, weak bass, and other bad things.

 

I have had quite a few big systems and never had a cap.I decided to buy 1 to see if there was a difference and there wasn't.Like said above,just upgrade the big 3.

 

what about for people running underdrive pulleys? im using the crank and alt pulley's. is there a higher alt that i can go to? my car is a 92.. is there a 140 amp alt that i can buy?

 

you can buy alts up past 300 amps you can also put over drive pulleys on the alt if needed

 

so i am assuming that an alt and battery is two of the big three what are the others

 

big three are major three electrical system wires under the hood

alt to batt
batt to ground
block to ground

it prevents bottlenecks in your charging system

 

ahh i got ya i will just replace those with some good old 2 or 4 awg wire

 

That's the idea.
And on the bigger alt note, and I'll add a disclaimer (I'm not positive about this), isn't there some credence to the "a bigger alt will put out less current at idle" rumors? I would think this wouldn't be a hard and fast rule, it would depend on the alt. But wasn't there a Ford alt. pulley that was a smaller diameter, so it would spin the alt faster? Anyone got info on this, or am I delusional.
Do I need to take a ruler to the junk yard tomorrow?

 

umm i think it depends on the windings in the alt.. another side note is that a 200amp alt doesnt put 200 amps 100% of the time. check what rpm the output is rated at.

 

my 280 amp from iraggi alts is supposed to put out either 40 or 60% of that under 1200 rpm.

ive also added a smaller pulley though that i made on a metal lathe

 

I started with the battery cause i figure it was cheaper than the alt. Bought a Optima yellow, and i just love it. I run 14volts almost all the time while running, and no more headlight problems. Well unless i REALLY push it. As far as the cap, is it worth using if you don't have any problems? Buddy of mine has a 1500watt sub amp and he said after he put in the 5 farid cap the bass was alot cleaner. Any truth to this? He had already upgraded the other stuff so his system was in tip top shape.

 

I noticed the cleaner bass

 

with only 1500 watts i would have just gotten an alt big enough to charge that amp alone and i wouldnt have added a cap

 

5 farads... how much do those run($) tho?? they cant be cheap if 1 farad amps are like 50 - 100

 

they're fairly expensive..the general rule among cap people is to use 1 farad per 1000 watts

 

he just bought the 5 farad cause of the badass factor they look way better that the 1 farad types, and he was all about the show.

 

yea it sounds like it

oh well if he's happy with it thats all that counts

 

yah i just talked to my buddy at the local stereo shop he said get a 1 farad cap and a battery that has 700 cold cranking amps and he said i will be all good

 

a better battery will always help...but you have to understand that a cap is basically a small battery that discharges and recharges quickly acting as a buffer for the electrical system.

your alt has to charge this buffer quickly and frequently for your stereo aswell as run any other options you have in the car. So if your alt isnt up to the task of supporting your stereo, heat, ac etc adding another small battery is only going to make it work harder and kill it sooner. Eventually you'll have to buy a new alt anyway so buying a higher output alt right away will actually save you money over buying a new stocker and a cap. Plus if you decide to sell the car you can take out the high output alt, and put your stock one back in and use the good one for your next application

 

NEEDAZ:

you are correct about the alternator thing, it is caused by the thicker wire needed in the windings for HO alterantors. It's more typical in 'upgrades' of OEM UNITS since there isn't much room for more turns.


CAP=wasted money

Maybee I'm just biased, but I'ved seen a good deal of electronic equipment and I've yet to see anything like the caps in car audio necessary for anything. If a 5000 watt laser power supply or 30,000 watt radar transmitter doesn't need one, I doubt a stereo in a car actually needs one. The only time I've heard of anything like that was for power management circuits used with electrical service for big commercial buildings and factories to balance inductive loads.

Although home audio operates at higher voltages, it is still DC throguh the power supply, there are no enormous caps in there and those amps work fine.

 

i don't think it is really for the amps its just so the stereo doesn't drain the battery so hard due to when the enitial bass hit hits it will draw alot of voltage from the battery thus taking away the voltage for other things such as your head lights or interior lights and when the cap is on there the cap takes to initial hit until the battery can catch up much like a line with a space in it when the bass hits the cap gives power for the amp for a milisecond until the voltage from the battery can travel down the power cable. that is what i got out of reading Richard Clarks article.

 

I’m not trying to be harsh here, but reading the last post I see we need to fill in some holes in your under standing of the theory end of things.
First:
“i don't think it is really for the amps its just so the stereo doesn't drain the battery so hard due to when the enitial bass hit hits it will draw alot of voltage”
The electrical system will supply voltage to a device. The device will “draw” current, not voltage.
“thus taking away the voltage for other things such as your head lights”
Again, what is “taken”, to call it that would be current, not voltage. It is VARY important to have a good strong under standing of how Voltage and Current are different and how they relate to each other. Kinda like HP and TQ. Voltage will be supplied to the amplifier at a constant rate (as long as the electrical system can keep up). The problem comes in when the system can longer supply the Current the amplifier is “drawling”. When you hit this point, you get voltage drop. This happens because of two things. Ether the alternator/battery has hit it’s limit, OR the system that delivers the power (this would include the power wire and its connections and the ground wire and its connections but not just to the amp, also the alternator wire and engine grounds) has hit it’s limit. You need bigger wire to carry more current, not voltage. This is why we need 4 gage wire in or cars. Now I just used the “P” word, POWER. Power is voltage times current, P=IE (P=Power, E=Voltage [electromotive force] and I=Current [C is used for Capacitance]) measured in watts. When your base “hits”, the amplifier will “draw” a lot of current. It becomes a low resistance load. If, when this happens, there is a shortcoming in the electrical system and you get some voltage drop the cap will come into play. It will try to keep the power supply Voltage at a constant level which means the cap will be “dumping” current back into the electrical system. Where did this current come from in the first place? From the electrical system. So now that the cap has “bled” off some if it’s potential power, where will it get more? The electrical system. The cap here is being used as a small sort term bucket for the electrical system. It empties fast and when it’s empty it needs to get filled back up.
Now with all that said, can a cap keep your headlights from dimming, yes. Will your headlights dim if your electrical system is up to snuff, NO. Caps will supply that sudden surge of current when needed but as soon as that happens the electrical system will need to charge the cap right back up which is just work for the system, it’s just happening a little bit latter. All your doing is postponing the “draw” on the system. And there’s more to caps then just how many farads they are. ESR is VARY important to.

 

ok well first off i was drunk when i wrote that second i do understand what you are saying about current and voltage i don't have a good understanding about car stereo and am still learning that is why i am asking these questions. as for just backing my self up i am a second year electrician apprentice so i have a understanding about voltage current and power. just don't know to much how it applies to vehicles the last post i was going off a post that was made on another forum so thank you for the info. and i do apologise for the bad proof reading i didn't say i was an english major. but thanks again and if im correct i should look for the lowest esr rating.

 

I was drunk once, and I swear that wasn't the girl that was there when I fell asleep. And yes, a low ESR is better, the problem is most cap suppliers don't list an EST in there adds. It seems the caps with the biggest problem are the larger caps (2F and greater) and the ones that are an odd shape for a cap (any thing other then tall and round).