How can I add voltage to a car electrical system?

I have a 14 volt car electrical system (standard) How can I increase the voltage back up to 14 and prevent it from dropping due to car audio? Adding a battery will only provide a small amount of time and therefore not provide a well made solution.

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ss30004 years ago
Perhaps rick is not aware of what an aftermarket audio system is capable of drawing. A moderate system is more than capable of drawing more watts than a factory charging system is able to provide during heavy loads. If a system draws upwards of 3000 watts at peak and the generator can only supply around 1000 then the voltage will drop because at that point the system is more or less relying on the battery, add in the draw from the rest of the system and the battery will struggle to supply the power even for a short amount of time. depending on your vehicle you could also look into adding a second generator to your motor.
Sounds like the only thing you can do is get a bigger generator and more batteries and look into your grounding. That is something that is often overlooked when someone installs a system. Look into getting some big copper grounding straps or use some amp power cables for the grounds. Maybe see if you can get the generator output to around 160 amps. If you can add another 90amp generator that would be 180 amps total which would be 2160 watts.
A car is 12V as standard, not 14.

confusing with 14 volts standard, but you can increase during car running


Well old post, but to increase an hold it will depend on battery power. Normal battery thats good will rest at 12.9 volts. Good charging system will maintain 14.4 to .5 volt while cars running. You are trying to increase your voltage but you will still have drop due to lessen they amps output. The stator will only give what it's got. You don't gain from it unless you got the amps to push it an keep it an some sort of external regulated source for field current. But in all of this you need battery's plain an simple. I started by going to junkyard like one guy said on here. Found the biggest factory ho alt an made it work..

In my car i done the same you wanted to do but I did make mine do 16 volt at a flip of a switch on a 110 amp cs130 . Also did dual rectifiers an 2 140ah battery's. But it could keep it up for 4 second before it go to 13.5. Now I have dual 280amp alts 4 rectifiers 3 140ah battery an I can voltage adjustable to beyond limits. I can hold 16 volt an go to 17 or 13.2 at the turn of a dial an maintain it with no problem .3 drop at full tilt on DC 5k.

getgcs (author) 4 years ago
Hey thanks for the help.. yeah so how do you make your current generator output more amps? I have all 0 guage grounding wires for the big 3 but what are copper grounding straps? Also do you know of a website with good alternators that arent as expensive as mechman alts? Thanks so much :)
ss3000 getgcs4 years ago
This is one of the few places I found where you can buy it by the foot
Just solder the terminals on and install.
You may want to check your local audio shops to see if they carry or can get it as well.
As for the alternator depending on your car you may be able to find something at your local junk yard or parts store for ones that might fit the mounts that are from other vehicles. Without knowing the car it's hard for me to say and I have been out of car audio for sometime so I don't really know of a good source either.

Found these too
actually found quite a few on ebay.
getgcs (author) 4 years ago
Any way other than that method?
getgcs (author) 4 years ago
I have 4 amps and a deck that displays the voltage. about 3000 rms total. I have 2 Hertz HDP4 150w 4ch amps, an alpine pushing 150rms to 4 channels and a Rockford 1500.1 I have 12 interior audison voce kv6 components and 3 W7 10' jl audio subs in a custom ported box. The main wiring I have is 0 Guage (Big 3 installed) and JL battery terminals. Yellow top battery and a tsunami 5 farad cap. 4 guage to all amps. My pioneer deck displays the voltage which reads 14 when car is on and 12 when it is off. This is normal. Now the question is instead of replacing my 90amp @2k rpm alternator is there anyway to prevent the voltage decrease... My voltage goes down to about 12.9 volts the lowest when the car is idle and I crank the system.
rickharris4 years ago
Your cars load j the battery with the engine running is less than zero (or the battery wouldn't charge)

Your battery is capable of providing 840 watts for over an hour (without charging)

You appear to have some serious wiring issues if your amp isn't operating as you think it should.

In general these are cause as I said before by high resistance limiting the current available. Beef up the wiring to the amp.

What wattage is the amp.

How do you know there is a voltage problem at the amp.

What do you want the voltage to be - Anything greater then 12 volts nominal will require extra batteries in series with the car battery (But may not solve your problem)

Are you wanting to increase the amps output by increasing the applied voltage? If it was designed to run in a car (on 12 volts) this may not be wise.
getgcs (author) 4 years ago
I meant 14 volts as the standard when the car is running and it looks like there is no other way to prevent voltage drops besides more batteries in parallel or a capacitor or a more powerful alternator... I have all this. Yes I do have a powerful system but I was looking for an out of ordinary way to keep the voltage where it should be without paying 400 dollars for a 300 amp alt.
rickharris4 years ago
Your not understanding the relationship between power, voltage and current. - the capability of your car battery should be considerable - Most will offer 30 to 70 amps for an hour without the engine running. 70 amps at 12 volts is 840 watts for an hour.

Your biggest issue in a car is loss through high resistance, this limits the current available and so the power.

You need the correct rated wire for the power used AND make sure ALL earth connections AND live connections are clean and well made.
framistan4 years ago
If your voltage is dropping a little when your audio system is turned on, it could indicate your battery is getting near the end of it's life. Or it could indicate corrosion on the battery terminals. Also if you wired up a sound system with too thin of wire could cause that. It could also be caused by your sound system is just SUPER BIG high powered and is drawing too many amperes from too small a battery/alternator system.
frollard4 years ago
The solution assumes that your engine is running, and you have a suitable alternator to create enough electrical power for your audio system. Consider you may need to upgrade your alternator and/or battery if they are worn out.

To prevent immediate dips in voltage, you can install a 1+ farad capacitor bank designed for car audio - near the amplifier. It will prevent some voltage dips that can dim headlights, etc.

If the car is not running, then you just need more, bigger, 12 volt batteries in parallel to the car's main battery.
Vyger4 years ago
I am confused, car (automotive) systems are based on 12 volts. Granted they often do have higher voltage but that is because in order for the alternator to recharge the 12 volt battery it needs more than 12 volts. So, you already have a battery in the car and it is a 12 volt battery. With the engine if off, everything is running on the battery, at 12 volts. If the engine is running then the alternator is producing current and that will usually be 13.5 volts. 14 sounds a bit high. Your car audio should have no impact on the voltage of the system. (unless it is pulling more power than what the system can provide in which case it should blow the fuses.

If you want to increase the voltage from 12 to 14 volts then run the engine, its that simple.