its been a while since ive been really big into car audio so i just have a quick question.
currently i am running 2 amps. combined im running about 700 watts RMS. i have a 1 farat capacitor on there right now (just had it left over from the last system) and im also using 4 gauge amp wire. my question is do i need the capacitor? if not i dont like how i had to mount it and would like to get rid of it.

 

Some will argue yes and some will say they are useless... With the F-bods I have never ran capacitors and have never had any problems with lights fading or anything like that since the charging systems on these cars are beefy right from the factory... I would ditch it unless you have light dimming problems or are running an SPL competition car...Just my .02

 

If your lights are dimming on loud bass hits don't bother with a capacitor. If your car's charging system is lacking upgrade by getting a high output alternator to fix the problem. Caps are just a band-aid and a waste of money.

LT1 cars have a 140 amp alternator stock. For whetever reason GM put a whimpy little 105 amp alternator in LS1 cars.

 

Some LS1's got a 102 amp

 

Capacitors are generally only for cars that can't handle the power being drawn from their batteries. Get an Optima Yellow top and you'll never have to worry about this kind of thing.

Optima is a much better investment, because you can use it for other things.

 

The battery doesn't mean a damn thing once the engine is running. Optimas are SOOOOO over rated and over hyped it makes me want to scream.

 

If the current demands of your stereo are just a little bit higher than what your car's charging system can deliver then a capacitor MAY help with dimming lights.

If the current demands of the stereo far exceed the capabilities of the car's charging system then the cap becomes an extra load on the charging system. It actually does more harm than good. Actually it doesn't do ANY good at all.

 

It really depends on what you are trying to get out of it. I mean if your electrical system is lacking I always suggest a HO alt first. The reason being this is the main sorce, where all your volts/energy is generated. If you are trying to use a cap cuz your alt is not up to par with your electrical needs I do not suggest using one to try and fix your problem. If you are using one to try and "smooth" out the voltage dips with an already upgraded electrical system that is fine. Adding a deep cycle batter really won't help much if any at all. Here is a thread from another forum where I an others had a discussion on caps, and other stuff.

 

caps are no more strain than more batt's and when they discharge, it will flow to where ever the voltage is lower. back down the + lead to the batt, to lights, to amp, where ever.

look into a big drycell battery. odessy has some good ones. stinger is good too, but you're paying for a name, because they have someone else make it for them. dry cells charge and discharge faster than lead acid batt's which will help you out a lot. that should be the first investment before the capacitor or alt.. and the alt before looking into caps. and the new rule is 1 farad per 10 amp draw i believe, because 1 per 1000 true watts doesn't hold to be enough. batt cap (kind of a hybrid deal) is one to look into.

 

A HO Alt should always be your first investment in a weak electrical system. A dry cell battery will not help.

 

I couldn't agree with you more. The alternator is the heart of the car's charging system. No capacitor or battery of any kind is going to benefit you more than a High Output alternator. Once the engine is running ALL of the car's electrical needs are supplied by the alternator. The alternator provides the juice while the battery becomes a part of the load on the charging system. Just like the stereo system is a load on the charging system. If you have some over hyped battery that seems to have cured dimming lights it's ONLY because the battery is discharging (like a cap) while it should be charging.

 

I'm not going to say caps are useless, cuz they are not useless, they are just misused. There are a few things needed to be done electrical wise for a dynamic aftermarket car audio system. One is a high output alt, another is electrical wiring upgrading, deep cycle battery and a cap.

Caps should be used, but only after the car's electrical system has already been upgraded. People use them to try and fix their electrical problems, instead of fixing it the right way. They are meant to help smooth out the voltage spikes (voltage dips/drops) in an already upgraded electrical system.

Now the alt is made to keep everything running/charged at around 14.4 volts. Now if the alt's continuous capability are exceeded, like from our aftermarket audio systems the volts will drop. The volts will drop untill it reaches the level of the battery, and the battery puts out only 12 volts. Regular batteries have a slow transient response, and deep cycle batters have an even slower transient response. Transient response is how fast a battery or cap can respond to the request of current. The battery and alt supply all the current that is demanded.

At this point your lights are starting to dim. Why do they dim? It's simple, cuz your lights are brighter at 14.4 volts than at 12 volts. Now here is where a cap can help seeing as it has lightning fast transient response. A cap stores current that it gets from the alt/battery, so it should be resting at around 14.4 volts. When the volts start to drop the cap will begin to discharge current that the alt could not supply. It will slow down the voltage spike, helping to supply current intill the battery's transient response kicks in.

Now the problem is the cap discharges all it has stored in a fraction of a second, so it's discharge wont even last a full second, not even close (this is why it can't fix your electrical problem). Now after it has discharged it will take the cap quite awhile to charge back up (I believe it's around 5 times constants worth of time to get to 99% for a 1 farad cap). So if you have another voltage spike while the cap is charging, it will discharge but it wont have much if anything to discharge, and is pretty much worthless untill it has fully charged.

Now adding a cap may in fact help your dimming problem, but it will not eliminate it. The cap will just slow the dimming down, so you may see an improvment in dimming by adding a cap. There is nothing wrong with your electrical system working in the way I explained, this is how it was made to work. Your battery is suppose to help your alt in times of need. The only problem is you may run down your battery cuz your alt can not supply all the current that is needed. This is why you need to start from the heart of the electrical system and get a HO Alt.

This is how it works believe it or not, and I'm not trying to sound all high and mighty (like some people have thought in the past). I'm just trying to explain how it all works so everyone has a better understanding of it all.

 

For 20$, you could upgrade your main chassis wiring and get way more benefit than a cap.

Then do your alternator.

A cap really should only be used to keep your amps happily powered.

 

ok i took my cap off and no dimmng problems. and by ho alternator how high am i supose to go? the car comes with a 140 amp.

 

what do i upgrade for $20