Dual Battery Setup Questions

[shotgun]

First I will say I know enough about electronics to get me in trouble and not much more.

A capacitor is used when there is quick spike in current draw. It acts like a low resistence battery, so it can react quicker to demand. As a side benefit they also smooth out the voltage (steadier).

I use a 38k MF 16vdc capacitor on the power side of my Crane Ignition (ever read thier instructions) just for those reasons.

A capacitor does store energy but not enough to power your system. The power in a capacitor still comes from your battery/alternator , it can't create power.

I think you would be better served getting a good alternator (not PEP Boys) that charges at low rpm. I use one from SVA that puts out a 100 amps at IDLE, 160a peak.He makes bigger ones that could power a city block!!!

A high output alternator costs and weighs less then more batteries if that matters to you.

Hook this to the isolator, run 2 of the biggest batteries that will fit.Oh, the batteries must match, ie same brand , type and age.My choice is Orbital 6 from NAPA , it is thier AGM type battery.

A capacitor is still not a bad idea, but now you can run smaller ones, maybe on the bass amp only?

Proper size wiring and good connection will go a long way also. Don't forget Noalox on all your connections.

 

[Phoenyx]

^ I agree with him^

 

[franknitticutlass]

Ok that sounds like the route ill go thanks

 

[shotgun]

I just wanted to correct myself on something, the NAPA is what I run in the race car. The battery I use in the Wagon (street) is the DEKA Intiminator: http://www.remybattery.com/Products/Dek ... A78DT.aspx

 

[84GP455]

He is still going to need to install some capacitors even with dual batteries. He may need 2 or 3 capacitors depending on how many amps he installs if the 6,000 watts is for real. It's true that capacitors don't make energy but they do store a lot of it which is where his amps will draw from, not the batteries, they will just replace the volts used from the capacitors. Look at any competition sound system and they will have more capacitors than batteries! A capacitor does store enough energy for your sound system for short spurts at a time, then is replaced by the volts from the alternator and battery.

 

[madmaxstyle]

Dual Battery allows you to play your stereo for extended periods of time without recharging, good for situations like if you're G Body is the center of attention at a party. Who wants to start their car every hour on the hour to keep yourself from needing a jump. Caps allow the amps to make peak power efficiently without losing voltage at the peaks. Bigger alternator is a must -most G Bodys only have around a 50-70Amp alternator stock. There's better out there up to 400amps if you go after market (some in the GM family on different applications such as the 3800 series engines) the hardest thing on the electrical system IMO is when your drawing power out of every other system to power your stereo (ie- your lights dim to the bass)

 

[84GP455]

I agree if you are using your stereo a lot without the car running dual batteries are a necessity. I rarely use my stereo for long periods of time with the car off. I see why you need dual batteries now. A second battery is never a good idea as it's just an added strain on the alternator unless you plan on running the system with the engine off. I have a 130 amp alternator and it is plenty of power for my system.

 

[shotgun]

'A second battery is never a good idea as it's just an added strain on the alternator unless you plan on running the system with the engine off. '

How do you figure? An altenator will only put out what it can, so it may take longer to charge 2 but no added strain.

Is your altenator always running at full to keeping up with your stereo? That is more strain to me.

Your start/car battery rarely is ever fully discharged, most is right after starting, so the battery just gets topped off.

The sense wire will regulate to load, topping off battery and loads (ign, lights, stereo).

Lights dim because you are taking more voltage then the charging system can provide.

2 batterys =more storage , less work for the alternator.

 

[Bonnewagon]

I know nothing about amplifiers in cars but I do know about boats. What we use are twin batteries with a selector switch, which can be set on batt-1, batt-2, both, or none. Shotgun, is that what your isolator does, or different? One battery is a cranking type and the other is a deep cycle type. The deep cycle can be ran down to totally dead, then recharged over and over with no damage. We use them for trolling motors, electronics,bait well pumps, anything that will possibly drain the system over a days fishing.If it does die, you switch to the cranking battery and be on your way. Lately I've been using Odyssy AGM type since they are a crank/deep cycle type combined. It sounds to me like this system could be used for powering amps and if you kill the battery- no sweat- just switch to the main to get started and recharge the aux on your way home. What do you think?

 

[franknitticutlass]

That actually sounds pretty cool. Im going to continue searching and comparing on the best method for a while.