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Big 3 upgrade

Thank you all for your responses.

@Will L. Thank you for all your insights. Everything you explained makes sense to me. Well... most of it anyway, your knowledge and understanding of electrical far surpasses most I am sure.
Yes, my username reads terrible. It stemmed from when my friends and I each created a gamer tag years ago taking our first initial (S=Steve) doubling it and adding force behind it. It has nothing to do with what, I am sure, everyone has running through their heads. I am just not very creative so it stayed when I went to more important things like trucks.

I should have prefaced this thread with a little more background as to why I was doing this upgrade. I am currently working on a sound system installation for my truck. When all said and done I will be right around 1000-1200RMS watts to 2 amps, one for door speakers and one for subs. A big thing in the audio world, at least from what I read, is to do the big 3 upgrade. Now, I have been told from others in regards to my install that the big 3 is not needed. I had a similar system in my 97 6.5 and it handled it decently without doing the upgrade. I did get dimming lights and would watch my alt gauge fluctuate a decent amount when I was playing music well above easy listening levels. :woot: So I do see some need for the upgrade, plus future add-ons.

Anyways, I started looking up installs and the only one I could find on the dual battery setups was to leave the stock charge wire in place to the little jump box on the driver side engine and run an additional one to the driver battery. Didn't really make sense to me but @WarWagon straightened me out there.

If I had more money, time and room I would put the batteries next to each other as Will L. suggested. I just don't see that happening with this install. But, from everything I have come to understand here, in keeping with stock location batteries. Would be to increase the size of all the wires and correct/add/change grounding locations.

I believe the stock wires on the truck are 2gauge, I bought 1/0 OFC. I know its not a major jump in size but I see it being sufficient. (I know there was reference to 2/0 gauge, so correct me if I am wrong)

The biggest reason for my wanting to do the big 3 was seeing that little charge wire coming off that alt and thinking to myself, If I am running a 1/0 gauge wire back to power two amps there is no way that little guy is going to supply what is required.

Again thank you all for your valuable input. This site and all of your knowledge is priceless.
 
On the 1/0- yeah that should hold plenty of energy monsters.

The name thing- nothing wrong with SS FORCE. I always thought Super Sport and something about forced induction. So maybe an SS Camaro with a turbo...
Adding the @ symbol so it would notify that it is a message to you specifically is a super cool thing on the forum now. However, the “a” before the ss makes a little swear word. Then the word Force after that, and maybe the fact that I heard a comedian around half hour before making jokes about prison rape... and that is how far in the gutter my mind was at the time.
 
Maybe should have started with audio as a goal. Big caps help the sudden draw for a good low punch.

So 1000w RMS is like 60amps aka ask the alt to power the glow plugs. Peak and efficieny figure to ballpark 60A. Two of them to need 120A at idle plus all other loads.

IMO an alternator upgrade (dual alt? ) as well as a charge wire upgrade replacement is in order just to keep up.

Engine off amp use???
 
WarWagon said:
Maybe should have started with audio as a goal. Big caps help the sudden draw for a good low punch.

So 1000w RMS is like 60amps aka ask the alt to power the glow plugs. Peak and efficieny figure to ballpark 60A. Two of them to need 120A at idle plus all other loads.

IMO an alternator upgrade (dual alt? ) as well as a charge wire upgrade replacement is in order just to keep up.

Engine off amp use???
Click to expand...
Yep, I'm with you on dual gen/alt being perhaps the best option, running together the demand would be split between them, running isolated also has it pro's too
 
I wouldn't do two alternators, I used to install sets frequently. Your far better off having 1 alternator sized appropriately, even if they do the external assembly design.

If you are think you draw too much power for the existing unit to supply, call a mfr like powermaster where you can speak to an engineer od designer. They do custom alternators frequently.
 
WarWagon said:
Maybe should have started with audio as a goal. Big caps help the sudden draw for a good low punch.

So 1000w RMS is like 60amps aka ask the alt to power the glow plugs. Peak and efficieny figure to ballpark 60A. Two of them to need 120A at idle plus all other loads.

IMO an alternator upgrade (dual alt? ) as well as a charge wire upgrade replacement is in order just to keep up.

Engine off amp use???
Click to expand...

I should have mentioned my goals before just asking about the Big 3.

Just to clarify the 1100-1200 watts will be the total of the two amps combined. 100x4rms to the 4 door speakers and 750x1rms to the 2 subs.

I do plan on engine off use. Not a lot but there are get togethers at the family cabin and my truck ends up playing the part of the jukebox. Just to clarify the 1100-1200 watts will be the total of the two amps combined. So from you math an additional 60A draw.

I don't want to open a whole can of worms but I've heard about 50/50 on caps. Some say they are worth it and other despise the name. I don't know enough to make an educated decision.

Also, just to clarify, you mention not hooking up anything new to the batteries. Would I attach my amp power wire to the + box on the side of the engine or am I missing something?
 
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Your stock alternator is 145 amps. If you do dual alternators correctly, there is nothing wrong with them. GM didn't just hook them up independantly, but instead used the ecm to control each one independantly. That said, 200 amp versions of your stock alternator are all over, I believe GM even offerred one. If it was mine, I would upgrade the charge wire at the alternator and install a fuse in it instead of the stock fusible link, connect your amp power supply to the junction block, ground to the block, and go with the factory dual alternator setup. I like power caps myself as it will definately ease the peak draw and even it out. For 1200 watts that is roughly 100 amps of current draw, so no small load, but not huge either. With the dual alternators I believe GM rates the junction block to supply that much power for upfitter useage, so why not give it a shot before you go cutting up the factory harness's to change battery cables.
 
THEFERMANATOR said:
Your stock alternator is 145 amps. If you do dual alternators correctly, there is nothing wrong with them. GM didn't just hook them up independantly, but instead used the ecm to control each one independantly. That said, 200 amp versions of your stock alternator are all over, I believe GM even offerred one. If it was mine, I would upgrade the charge wire at the alternator and install a fuse in it instead of the stock fusible link, connect your amp power supply to the junction block, ground to the block, and go with the factory dual alternator setup. I like power caps myself as it will definately ease the peak draw and even it out. For 1200 watts that is roughly 100 amps of current draw, so no small load, but not huge either. With the dual alternators I believe GM rates the junction block to supply that much power for upfitter useage, so why not give it a shot before you go cutting up the factory harness's to change battery cables.
Click to expand...

My plans exactly to ditch the fusible link and run a 1/0 fused instead. I have made the cable now just needing to install.

I will be leaving the majority of the under hood wiring alone, but take the advice given and correct some of the grounding points with the 1/0 gauge I purchased.
 
Idle output of the stock alt wouldn't be enough. I recall the Dmax injectors and trans computer are power hogs. Engine off use should have deep cycle battries. Charging them via the engine - again bigger alt. AGM can take all it can put out during bulk charging. I have seen 50A limited only by small long run of wire from my 60A converter into Lifeline AGM batteries. Yeah, genset has to open it up to power that.
 
WarWagon said:
Idle output of the stock alt wouldn't be enough. I recall the Dmax injectors and trans computer are power hogs. Engine off use should have deep cycle battries. Charging them via the engine - again bigger alt. AGM can take all it can put out during bulk charging. I have seen 50A limited only by small long run of wire from my 60A converter into Lifeline AGM batteries. Yeah, genset has to open it up to power that.
Click to expand...
Power draw at idle should be under 20 amps for an lbz. The lbz came stock with essentially an ad244(call it an ar44 or something, but it's just a next gen ad244), so idle output will be 90-100 amps, put 2 on it and he's got more than enough. You can also get the high output alternator pulleys which are a good bit smaller and increase alternator speed for increased idle output.
 
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