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dual alternator setup

Printed From: the12volt.com
Forum Name: Car Audio
Forum Discription: Car Stereos, Amplifiers, Crossovers, Processors, Speakers, Subwoofers, etc.
URL: https://www.the12volt.com/installbay/forum_posts.asp?tid=100872
Printed Date: May 15, 2024 at 3:56 AM


Topic: dual alternator setup

Posted By: 3000dclass
Subject: dual alternator setup
Date Posted: January 07, 2008 at 10:52 AM

I am thinking about adding a second alternator to my truck. It has a perfect place to install it, right where the a/c compressor would go I can install it since it has no a/c. Since it would be an easy install, would it be difficult to have a second electrical system dedicated to my system? Has anyone ever done this because the couple of places where I live won't talk to me about doing that, they sound like they are scared to try such a thing.
The setup would be on a 1997 gmc sonoma, v6, w/ two Rockford Fosgate 1500 bd amps, and two JBL 15" subs, and a 1 farad cap.
Thanks



Replies:

Posted By: greenbroncoguy
Date Posted: January 07, 2008 at 12:00 PM

I don't see why it wouldn't work. It shouldn't be that hard to keep everything isolated from the factory electrical system - with the exception of grounding; that is where if you have a problem, it will lie. Since you will be using the metal chassis as your grounding medium(you will have to since the alternator will probably ground through it's case, through the engine block, and finally back to the battery), both batteries, and consequently electrical systems, will share the same ground.

I do not posess enough electrical knowledge to know what negative ramifications this would have, but it is an interesting topic of descussion. Hopefully someone else will chime in...





Posted By: sedate
Date Posted: January 07, 2008 at 6:11 PM

3000dclass wrote:

would it be difficult to have a second electrical system dedicated to my system? Has anyone ever done this because the couple of places where I live won't talk to me about doing that, they sound like they are scared to try such a thing.

From a strictly technical standpoint, creating a 12v system like this wouldn't really be that hard. Engineering everything to fit would be incredibly difficult however.

I think the problem is that it is simply easier to beef up the primary electrical system.  I'm having a hard time imagining why building an entire secondary electrical system would be less expensive - or even materially easier - than dropping in a rewound alt and a new deep cycle battery.

It's not that it isn't possible, it just isn't practical or cost effective.



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"I'm finished!" - Daniel Plainview




Posted By: jmelton86
Date Posted: January 07, 2008 at 6:42 PM

If building the bracket wasn't a problem, would having both alt's grounded through the frame pose a problem?

What if you could isolate the 2nd one from the frame -of course creating a very unique designed bracket- and have the amps/etc... grounded straight to it's case -via BIG cable? Is this practical, of course if they both can't be grounded through the frame?

Please excuse me. I'm trying to think hard again...



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2013 Kia Rio -90a alternator
DDX470HD GTO14001 GTO1014D (x3)
Big3 in 1/0G
1/0G to GTO14001




Posted By: 3000dclass
Date Posted: January 07, 2008 at 6:43 PM
Sedate- well I've usually seen high output alt's runs well north of $200 and I don't really have that kind of money to spend on an alternator. I do have a Red Top Optima already in my truck, so I think that will work fine. As for installing a second alternator, I will try to get a pic of what I am talking about, because the place where a a/c compressor would be installed is empty, and putting an alternator their should be a drop in fit, like changing a stock air filter element to a k&n air filter.

But about the ground issue that was previously mentioned, I'm not really clear what you are talking about, but it does sound like that could be a problem, i'd like it if someone could elaborate on that...




Posted By: jmelton86
Date Posted: January 07, 2008 at 7:11 PM

I highly doubt it'll bolt right in...



-------------
2013 Kia Rio -90a alternator
DDX470HD GTO14001 GTO1014D (x3)
Big3 in 1/0G
1/0G to GTO14001




Posted By: sedate
Date Posted: January 07, 2008 at 8:57 PM

3000dclass wrote:

well north of $200 and I don't really have that kind of money to spend on an alternator. I do have a Red Top Optima already in my truck,

I can assure you that trying to graft a secondary, isolated 12v electrical system on top of your cars' existing electrical system will, all technical issues aside, cost you several times this figure.  Please remember, that you also have to add a second battery (unless that Red Top is a secondary, this is unclear from your posts) and all sorts of wiring.  I usually figure wiring runs up to 20% of a projected budget - this type of project might be significantly higher.

My understanding of traditional mutli-alt systems in limos and strech-Hummers or whatever is that they are wired in such a way to produce huge amperage at 12v - there isn't an isolated secondary system.

Seriously, I applaud your ingenuity and inventiveness here, but I think your trying to create something much more complex, expensive, and ultimately unreliable than you need.  You will not be able to simply hook up your amps to your new "drop-in" secondary alternator, and there maybe some technical issues with the a/c belt spinning properly for an alternator to generate proper voltage and output.  Perhaps not, but this is an important area for you to research.

jmelton wrote:

I highly doubt it'll bolt right in...


Of course I cannot be totally sure of your overall level of technical skill, but I can assure you,  jmelton is right.   Dropping in a second alt will be a far, far more arduous process than - and this is a great comparison dude - swapping an air filter.



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"I'm finished!" - Daniel Plainview




Posted By: big sexy lac
Date Posted: January 07, 2008 at 11:22 PM

okay after reading both topis this is what i think im not trying to offend or wiz anybody off this is just my opinion.

you said you already have a red top right? so thats done.

you said you already built a custom box right? so thats done.

you need to decide if your going to mismatch the amps or go with 1.

why do you think you need to upgrade or add a second alt? if want sound quality

the custom box and subs are going in 4 sure so if you decide to add or remove an amp. then its gravy.

im just saying ive seen alot of cars and trucks with more subs and amps than what your working with and with just 2 batts. under the hood. no big three no rewound alt. and no secondary electrical system, and just have their lights dimming a little bit!

my opinion install what you got and go from there. again this is just my opinion!



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WELL?




Posted By: dominick
Date Posted: January 27, 2008 at 10:33 PM
you get my PM 3000dclass?





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