Alternator

The answer to this is: If you want to upgrade, be careful higher output alts are a VERY spendy deal and unfortunately nearly uncharted waters. our 2 acclaimed leaders here have looke dintoit, but to my knowledge neither of them ever got an high output alternator going.

Thatsaid, you'd be amazed at how well you can get by without...
 
Thanx, Just curious cuz im getting an amp that runs at 1000 watts rms, Im geting a 2 farad cap to help, so there isnt as much of a strain on it.
 
a bit of advice on caps.

Things can either make power or take it, and caps do not make it... essentially they're a device, and not 100% efficient, therefore they can actually make current draw issues worse.

Thatbeing said, I've been daily running 1.5kw plus for wellover a year with no issues. Look into upgraded grounding, though makes a big difference.
 
Well i know that capacitors store a charge, i know they would at least help not putting so much strain on my alternator. just about everything with electronics is not 100 percent accurate, Most things are essitmated, or rounded off for better numbers. What looks better 903 watts, or 1000, lol
 
SP33D said:
what if im gonna be running amps that add up to like 4500 watts rms?


extra batteries are your only hope. caps won't do s*** for you, except hurt your system, since there won't be enough power coming from the alt to support everything anyways. you may also want to consider having a 2nd alt built for your car, and have the stock one just for the car and the 2nd one isolated to the stystem. go talk to a reputable stereo shop about that. if they look at you funny, run away(laugh) if they know what they are doing, you are going to need the extra juice. at least a 200 amp alt and a pair of good batteries for that system. it can be done on the stock system, but you're gonna burn through batteries very quickly.
 
nautical2086 said:
Well i know that capacitors store a charge, i know they would at least help not putting so much strain on my alternator. just about everything with electronics is not 100 percent accurate, Most things are essitmated, or rounded off for better numbers. What looks better 903 watts, or 1000, lol


true, capacitors store a charge, but they don't store much. and what they do store is generally not enough to help a systems for over .1 seconds. plus add in the resistance they cause, depending on how it's hooked up, and you will actually lose voltage at the amp, just from adding in the cap. every time you break the main power wire, you have increased the resistance in the power line. if you break the line, put on a ring terminal to the cap, use another ring terminal for the power wire going to the amp, you've just added enough resistance to lower the voltage almost .5 volts with a reasonable amount of current flowing through the line.
 
nautical2086 said:
Thanx, Just curious cuz im getting an amp that runs at 1000 watts rms, Im geting a 2 farad cap to help, so there isnt as much of a strain on it.

What amp are you using?

Caps hold a charge yes, but to be a bit more descriptive, they are intended to resist a change in voltage. NOw a cap can only charge to a voltage that is being supplied to it, so if the alternator charges the system to 14.4 volts, thats as high as the cap can have. Now one would think that this means that if the cars system has a large draw, that the cap will push out its power as soon as the voltage drops below 14.4 volts. This is true, it will, but it will release an almost unmeasurable amount of power because of its own internal resistance. Unlike the ideal, in the real world of electronics everything has resistance and so does the capacitor. So even once the power of the car drops below 14.4 volts the voltage has to drop low enough to overcome the capacitors internal resistance before it puts out enough power to be usefull. So tyypicly, by the time the car's voltage has dropped low enough to see dick from a capacitor, the battery has already cought the system and is now powering the amp, and recharging the cap, which still has done nothing.

The other problem with caps is that unlike what people think, they do not relase all of there charge at once or even as needed by the amp. The is basicly drawing current, however, caps don't give a damn about current, they care about voltage. Because of this, if the amp needs 50 amps but the voltage is still at 13, the cap does almost nothing. Caps put out power based on voltage drop so to get the maximum out put of a cap, the voltage would have to drop to zero. Since the car is never going to go that low and infact it not going to go under 11 volts, the cap will never produce more then a small percentage of its actualy capacity to help the system.
 
got wake? said:
extra batteries are your only hope. caps won't do s*** for you, except hurt your system, since there won't be enough power coming from the alt to support everything anyways. you may also want to consider having a 2nd alt built for your car, and have the stock one just for the car and the 2nd one isolated to the stystem. go talk to a reputable stereo shop about that. if they look at you funny, run away(laugh) if they know what they are doing, you are going to need the extra juice. at least a 200 amp alt and a pair of good batteries for that system. it can be done on the stock system, but you're gonna burn through batteries very quickly.

well.. assuming that i wont beat the living crap out of my stereo equipment.. would a rewound alternator get the job done?

also.. unless i want to listen to music while my car is off, what purpose would an extra battery serve as opposed to a cap? batteries, just like caps, as you know, only store power.. not create it. adding more just makes the charging system work harder trying to keep them charged. another battery is a load not a supply.
 
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SP33D said:
well.. assuming that i wont beat the living crap out of my stereo equipment.. would a rewound alternator get the job done?

also.. unless i want to listen to music while my car is off, what purpose would an extra battery serve as opposed to a cap? batteries, just like caps, as you know, only store power.. not create it. adding more just makes the charging system work harder trying to keep them charged. another battery is a load not a supply.


you can't just rewind the protege alt due to the 2 part voltage regulator. if you do, you are probably going to fry your ECU, at least that's what one of the places that makes stock harness interfaces told my buddy's alternator shop. you could just replace your stock harness with another one and not use the factory plug, however there have been complications with that as well.

extra batteries store WAY more than a cap. with a huge system, playing it at full volume for 20-30 minutes could kill a single battery, even with the car on. multiple batteries will keep the voltage closer to 12.5-13 volts much longer than a single battery. with the extra batteries comes extra maintainence to ensure they have a reasonably long life. weekly trickle charges is a good idea with multiple batteries that the alt cannot charge on it's own. you're also going to need a battery isolator for multiple batteries. adding another battery requires more current to maintain them on a daily basis, without any draw from the batteries. you'd have to learn to play your system loud for a while, then back it off to let the alt charge them up a bit before cranking it again. invest in some good voltage guages to monitor your batteries.
 
all of that said, Did you notice the part where my normal stock alternator has been handling 1.6kw DAILY for a year and a half?

My battery really wasn't even showing signs of weakness when I replaced it about 6months into that, but I got a deal on an optima so I figure di might as well preemptively upgrade.

INfact, to my knowledge I'm pretty sure Wakey wasn't running much more than an optima and his stock alt as well with sometimes upwards of twice that power. Do a search, there's quite a KW+ club who's been getting along just fine on stock alternators...
 
The other option, and not one I have seen exlored, is a second alternator that powers only the audio system. Will be a pain to fit under the hood though.
 
Poseur said:
INfact, to my knowledge I'm pretty sure Wakey wasn't running much more than an optima and his stock alt as well with sometimes upwards of twice that power. Do a search, there's quite a KW+ club who's been getting along just fine on stock alternators...


nautical2086 won't need to worry about beefing up the electrical system; however, SP33D has some power hungry zapco amps and is going to need something more.
 
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