Im runnin a 1800 watt amp and my headlights are dimming?

And, once again, Gravity writes a 2 page answer that is completely wrong. Pay no attention to this fool, he thinks he knows much more than he really does.

Im sorry bit Fred, Gravity is right on this one. When the vehicle is on, all requirements for power are take care of by the alternator, when the lights dim, that means your alternator is doing all it can, and is now dipping into the battery, but in doing so, it is shorting out everywhere else, hence why your lights dim. A capacitor is simply a band aid for a weak electrical system, in the end you are going to need a better alternator that can provide more amp's. I would suggest somthing between 140-160amps, that should be enough. Also doing the big three simply depends on what batter and alternator you have. There is NO POINT in doing it, if you have the stock battery and alternator. Sure more "water" can go through a fire hose, but it doesnt matter if you cant provide all that extra "water". If your putting out 12v (jsut an example) and you have wires that can handle 12v, and wires that can handle 100v, whats the point in getting the 100v wires, if all your putting out is 12v???? See what I mean? So get a new alternator, get a yellow top batter, do the big three, and you will never have to worry about this problem again.

Doing the big 3 is NOT a wasted step, nor does it only benefit the cable sellers. Think of it this way. Will more water travel through a garden hose, or through a fire hose? With the Big 3 upgrade, you will have more power traveling through the cable. I would definately do this first, before anything else. If you get a high output alternator and a bigger or second battery, the cables will be your weakest link.

Capacitors only give you a very short burst of energy. Cap cells spread the energy over a longer period of time. But both require energy to be fully charged first.

The only part that generates electrical energy in your car is the alternator. If your lights are dimming, it means that the voltage in the system is dropping to about 8-10 volts. This is not good for the car and the computer system in it. Cap cells simply borrow energy from the past and put it in the present. But this energy has to come from somewhere to begin with. And that's your alternator.

Look at this math, 1800 / 12 = 150 amps. Your music system is pulling 150 amps from the alternator and probably also dipping into the battery supply. You need to replace your current alternator with the one that can give you what your old alternator gave you, PLUS 150 additional amps.

Doing the big 3 is only good for those who sell those cables. The actual benefit to your system from that upgrade is negligible.

If you are not playing your system (and you shouldn't) with the engine off, you don't need another battery or a more powerful battery. This extra capacity in the battery is also hungry for energy. The main purpose of the battery is simply to start the car. If you can start your car, then your current battery is sufficient.

Once the engine is running all the demands for electrical power go to the alternator. When you over load it, it will overheat and you will end up having to replace alternators every year or so.

Ok, did I make my case about you needing a more powerful alternator?

Good. Make sure you get all the electrical upgrades done by people with experience doing such upgrades. Start with your dealer first, then look for auto electrical shops.

I’m speaking from 8 years of experience in fixing electrical issues on cars and trucks.

After you do the big three that is linked in the other answer I would suggest installing a extra car audio style battery. (Stinger, kinetik, XS power, shuriken) forget the capcell, it's a over priced gimmick.

My bad didn't have time to get in to this yesterday .

first need to know make and model of car so can search to see what altenator is in the car already and if you can run the car take a volt meter check your voltage at the amp and at the battery should be the same around 14.4 volts if not do the big 3 http://knowledge.sonicelectronix.com/car-audio-and... .

if you getting 14.4 then id look to get an 140 amp alt.

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