Has anyone tried this?

[Beerdrnkr 5,000+ posts]

I don't know how common or uncommon this is but has anyone ran a power wire from their alt. to their battery under the hood and ran a 2nd power wire from the alt to their battery in the rear. I know someone who's currently doing this and it's working great for him. He's running 4000w and never gets below 12v with a stock 90amp alt and battery up front and 2 nsb-90's in rear.

Or would it be better to do it the regular way and run parallel from the front battery to the rear?

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[mlstrass 5,000+ posts]

Shouldn't make any diff as the alt is still charging both batts...

 

[JLJunkieMX107 10+ year member]

Theres no way hes getting the full 4000 watts with that alt:fyi:

 

[Beerdrnkr 5,000+ posts]

Actually he's getting about 3800w. Would the way he has it charge the batteries quicker or does it not make a difference.

 

[Beerdrnkr 5,000+ posts]

Actually he's getting about 3800w. Would the way he has it charge the batteries quicker or does it not make a difference.

And I think that's at 1.8ohms nominal or something like that.

 

[XanderMoser 10+ year member]

Would the way he has it charge the batteries quicker or does it not make a difference.

Well, I suppose the current going to the rear battery has less wire to go through....and the wire going from the alt to the front battery has to pass less current. So in theory it would actually be better in my opinion to do it his way.

But I don't have a ton of experience hooking up extra batteries and such, that's just my view based on electrical theory.

So someone else can hopefully chime in here too

 

[Beerdrnkr 5,000+ posts]

Anyone else have any opinions or experience doing this?

 

[lostdaytomorrow 10+ year member]

It should be just fine, just make sure to fuse it of course.

 

[Kriszilla 10+ year member]

Actually he's getting about 3800w. Would the way he has it charge the batteries quicker or does it not make a difference.

Assuming 100% efficiency (which is impossible, it's usually 70-80%) at the amplifier, with a 90 amp alternator and 14.4 volts the continuous RMS potential would be 1296 watts.

He's not seeing 3800 watts, he's only starving his amplifier.

 

[BassBallin]

i might have to try this

 

[Beerdrnkr 5,000+ posts]

He actually had it clamped and that's what he was getting. People might not believe me but it's true. I've noticed in a few systems where people haven't upgraded there alt and still get most of the power out of their amps. I saw someone with 4 batteries and a stock alt. on a 40.1 and he was getting most of the power out of it too.

 

[twisztdauthorit 10+ year member]

why not just get a HO alt instead of all those batteries... Its healthier for the car and instead of 12v from batteries, youll get upto 14 off the alt...

more voltage= more power

all those batteries gonna weigh your ass down too

 

[Beerdrnkr 5,000+ posts]

why not just get a HO alt instead of all those batteries... Its healthier for the car and instead of 12v from batteries, youll get upto 14 off the alt...
more voltage= more power

all those batteries gonna weigh your ass down too

I'm actually only replacing the battery up front and adding one to the back. That wiring was just an interesting concept and it was working well for him so I was curious about it. I also might have my alt rewound which could help. I'm only running 2500w so it should be too bad.

 

[audioarsonal 10+ year member]

The only time I seen someone run a seperate line to the back was because the alt was externally regulated so when he would go into the lanes he just disconnected the wire to the front battery and uped the voltage to the back batteries as to not damage the vehicles electrical system.And when your friend got "clamped" where did they clamp and what readings did they take.Its all physics it takes power to make power and a stock electrical isn't made to run a 4000 watt amp without clipping it to death!

 

[buildmeabox 10+ year member]

Its ghettoy but it works, with a battery isolator you will achieve isolation between your starting battery and auxiliary battery. When the vehicle is running the battery isolator will charge both batteries as long as there is a load. Under heavy loads, auxilary battery for your car audio, current will go directly to your alternator output. All your doing is using both batteries to run your car and your stereo.

If you play your music with the vehicle off you will drain both batteries, longer run time, but if you install a battery isolator only your aux. bat. will drain and your starting bat. will be fully charged.