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Okay, I have a 750 Watt Amp and 2 10' subs in my car, and this is going to be the near 6th time I (and my brother which is the previous owner) have to replace the alternator in this car and I'm getting sick of it. I've heard that buying a farad capacitor can solve the issue, but what size would I need to buy and is this an effective solution?

The point of a cap is to ease the drain on your battery, since the amp(and through it the subs) will require a varying amount of electricity to power. Btw, a Farad is a unit of measurement.

The power required will peak, and have low spots as well; my understanding of the capacitor is that it will help to stabilize the drain on the battery, as the capacitor will be drained prior to the battery itself, meaning the "peaks" or high points in electrical consumption, will first drain the capacitor, and then the battery. This gives the battery a buffer, for the larger "hits" of your bass.

It doesn't sound like an alternator problem to me man. There are people on this board(and many others elsewhere) that run bigger setups on the same alternators. I think the problem lies elsewhere in your system, if the alternator is failing repeatedly.

Oh okay. Would you happen to know what I should check in order to tell what is killing my alternator repeatedly?

MrMazda92 wrote:The power required will peak, and have low spots as well; my understanding of the capacitor is that it will help to stabilize the drain on the battery, as the capacitor will be drained prior to the battery itself, meaning the "peaks" or high points in electrical consumption, will first drain the capacitor, and then the battery. This gives the battery a buffer, for the larger "hits" of your bass.:

Close, it's to ease the sudden drains on the alternator. Alternators aren't designed to handle a sudden high surge of power. Batteries are just storage mediums, they'll ease some of it, but the aren't high-discharge mediums. They don't get damaged (they just don't like to be completely discharged; see deep-cycle). Remember that the alternator is there to run everthing in the car, and keep the battery charged. You should not be using your battery power unless your motor isn't running (or say at idle if you're drawing that much power, the battery will suppliment)

MrMazda92 wrote: It doesn't sound like an alternator problem to me man. There are people on this board(and many others elsewhere) that run bigger setups on the same alternators. I think the problem lies elsewhere in your system, if the alternator is failing repeatedly.

If you want to see if you have a problem with your system, get a voltmeter, you'll see when driving and your system on if your alternator can keep up or not, or if your alternator can't keep on even if your system is off. If you're alternator can't keep up, you should see your headlights dim with every hit.

Indeed, I can a 720w amp, a CarPC, and a 1200w inverter for some of the CarPC plus the PS2, and never had a problem. I had a Millenia 110amp and I actually sat on the side and that I never installed. A capacitor is only a band-aid fix unless your running A LOT of power, 750w isn't a lot. You're running a GS, so the 90amp should be plenty.

What would cause the crashing of these alternators then? My charge light will pop on for about 1-4 minutes, then shut off and come back on shortly after. When it goes on, I can see the headlights dim down a small bit and the dash also.

Charge light is low voltage, the headlights would definitely him at that point. Does it do it only when the system is on? Has it done it while the system is off?

Umm these aren't 'Champion' alternators are they? Anyway for around $150 you can get your alt beefed up to put out a lot more amps just don't go too big. I was going to go 160amp but from what I've been told it's a lot more HP drain. My guess is that 110 to 120 would work fine.

Well, the alternator was just exchanged under lifetime warranty (it's covered in oil so there is definitely a different issue that could of caused it to die) and I never did try to test it without the system being on though.

Heh, my battery light came on and off for months after I bought the car, then stayed on for over 2 years. Battery tested fine, alternator tested fine... Turns out my harmonic balancer was slipping slightly, and apparently only while driving... It makes sense I guess, that the crank moving slowly at idle would cause the alt. to test well, but undercharge while actually driving.

That is a pretty stupidly unique case though, I'd hope. These guys'll have you covered for testing!