well i have two amps. the sub amp is pushing maybe 380x1 one. ive been slowly getting everything ptu togethoer and i just received my joe fox box.

my question is....when i hooked up a friends sub, bridged, my lights dimmed horribly everytime it hit. even worse when the truck was on for some reason.i dont want this to happen when i get my subs in next week. i plan on getting two jl w3's and then maybe upgrading the amp later.

i know there are two things i can do, change out the big 3, or get a capacitor. has anyone here changed out thier 3 wires? i believe its two grounds and one positive in the engine bay. both routes will require about the same effort to me. but which would be the better way to go? will changing out those 3 wires really solve that problem just by itself? the ligts dimmed BAD. i dont see how upgrading the guage will completely get rid of the problem. or should i just not bridge it? or what? i plan on running the amp at around 80%

 

i think if you make the wires a smaller guage it will help. i know with all that power you should have a small guage wire. What are you using now?

 

a SMALLER gauge? [sm=confused06.gif]

i have a size 8 guage wire going to both subs from the battery and as the gound.

 

You need to have big enough wire and you need more power. Either more battery power, caps, whatever it takes.

That post about smaller wire is just insane.

 

i figured, i think im just going to get a cap. i looked at the alternator wires and they aren't tiny.i had more power in a honda once, with the power and grounds wires a fraction of the size of the ones in my truck.

 

Magnum is trying to set your truck on fire..... Dont do that...On second thought, maybe he just meant a smaller number...yea...i hope....

I never run anything smaller than a 4AWG, period. A cap will help with the problem, but LARGER wires and an Optima battery will definitly help too. Try running some 4awg and get back to me...

 

but i just wired the whole damn thing with this guage. anway the guy who i bought it from said it was 4 guage but it looks like 8 to me. it didnt say on the box. the guage on there said "xtreme guage" ha.

 

I know, I know.... But the cable does not have a number on it followed by AWG? This seems odd.... Can you take a pic of one of the ends next to a penny so I can get an idea of the diamater of the cable?

 

I posted this on another forum but most of the info applies to what has been discussed here too. If some of the stuff doesn't apply to what was asked here just ignore it:


Capacitors do work for what they were intended to do. Their intention is to store energy to supplement your power supply during short periods of voltage drop.

Your electrical system in your vehicle is run off of the alternator at 13-15v depending on the vehicle and the current load. The bigger the load the more that voltage will drop. When your amplifier pulls enough current for the alternator to put out less than 12.6v your vehicle switches the reserve system(battery) on to help provide power. There is a short delay here because batteries are slow at providing and receiving charge and if your demand is great enough you can drop quite a bit below 12.6v. Once the battery kicks in you will jump back up around 12v. This puts a lot of stress on your charging system and has the potential to harm things in your electrical system. If it drops low enough(sub 9v IIRC) your vehicle can even turn off.

Capacitors work different than batteries in that their charge and discharge is much quicker. This allows them to help during these very short voltage drops caused by the dynamic current draw of music. However, they do not fix your problem. The problem isn't your headlights dimming. That is just a natural function of running on a lower voltage. The problem is your alternator getting exhausted to the point of the battery needing to help out. Adding the capacitor does very little to reduce the stress on the alternator and electrical system because it is inline between the battery and amplifier. This helps it protect the amplifier from these current drops and to a much smaller degree the rest of the system by giving the current hog some juice to help prevent it from pulling the system down even further.

This fix really is just a bandaid fix. Putting a bandaid on a broken arm when you have a bone sticking through the skin doesn't make it better. What you really need to do is replace the alternator with one that can provide more current. Someone mentioned the computer in Rams does not like this. I am not sure I fully believe that because your voltage should remain in the stock 13-15v range that vehicles are comfortable with. The computer shouldn't even notice it. The difference is they can provide more and as a result more power.


If you want to test if you need a new alternator get yourself a dynamic RMS voltmeter and measure the voltage at the battery during your regular use. If you are dropping below 12.5v you are exhausting your alternator's supply. If you are staying above ~11v you should be fine with only a little bit of extra wear on your alternator and battery. If you are dropping below 11v but staying above ~10v you are putting quite a bit of wear on your alternator and battery. If you are dropping to or below ~10v expect to be replacing them real soon and don't be surprised if you have problems elsewhere in the electrical system.

There is no generic formula of xxxx watts needs xxx farads of capacitance or an xxx amp alternator. All vehicles use different sized alternators and draw different amounts of current. Your alternator will always provide a little bit more current than your vehicle needs but this extra varies greatly vehicle to vehicle. You can however figure out how many amps your addons need. Take the wattage of your amplifiers or other equipment and divide that by 13. Wattage = amps x volts. We are dividing the wattage by the low end of ideal voltage. Take the amperage answer you get and find 2/3s of it. This is a rough estimation of how much average current you will be pulling for your amplifier. You will have dynamic peaks above it and valleys below it but for the most part your amp will draw this much current. Adding at least this much current will be beneficial. If you can add more and do not mind sacrificing the horse power then go for it.[/align]

 

I Can't Believe I Actually Read That Whole Post.. Must Mean It Was Interesting. So The Spin Question That You Did Not Necessarly Answer Is..

Is A Cap Actually Worth Investing Into.. Or Is It Best To Replace Your Alteranator With A Higher Output..???

You Show Both As An Option / Bandaid... But What Is A Solution If Your Amp Flat Out Wants More Juice.