got a question about electrical system

[rockmo 10+ year member]

i have a 91 gmc fullsize, 4.3 v6, with 105 amp alternator on it. fixin to do big 3 with 4ga running from alt to batt, and 2/0 ga for the grounds from motor to frame and frame to batt. also going to run 2 runs of 1/0 gauge to the group 34 exide spiral cell blue top in the back.

have a swiss audio mono block that is 2000 rms, pushing 1-15 inch memphis mojo d2, and going to put a 4 channel(eclipse hopefully) in there to run my comps active.

questions are.......

will i need to go up with the alternator amperage, and if so how high?

and should i go ahead and run a 2/0 ga ground from the gr34 battery in the back to the frame?

also, while running two batteries like this, do i need to do anything special to get the rear one to charge? or will running the 2 runs 1/0 from front to back be good? have heard of people using a battery isolator....not sure what that does, but if i need it i will get it.

any help will be appreciated, and i hope to get started on the install/box build/amp and xover rack this week.

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[fbi90909 5,000+ posts]

if the 2 runs of 1/0ga you are running from front to back involves 1 positive and 1 negative then it is not necessary to ground the rear battery to the frame.

as for your going up alternator amperage i don't understand that question.

a battery isolator is a small unit you mount into the run of wire going from the front battery to the back battery. what it does is it basically isolates your rear battery from the front battery, for instance w/o an isolator your car's components will be running off both batteries. with the isolator your car components will be running off of the front battery while allowing the rear battery to be used to w/e you have hooked up to it.

a good use for such isolators are for those that like to play music with their car turned off. if the car is turned off and your playing music only the head unit would be taking power from the front battery. while the amps connects to the rear would drain the rear battery. with that you wouldn't have to worry about having a dead starter battery.

 

[05AztecRed 10+ year member]

i have a 91 gmc fullsize, 4.3 v6, with 105 amp alternator on it. fixin to do big 3 with 4ga running from alt to batt, and 2/0 ga for the grounds from motor to frame and frame to batt. also going to run 2 runs of 1/0 gauge to the group 34 exide spiral cell blue top in the back.

might as weill do the big 3 in 1/0 as well. If you're spending all that money to do the rest of the system in higher gauge wiring, it won't cost much more to add a few extra feet.

will i need to go up with the alternator amperage, and if so how high?

Most likely, but that will depend on how hard you play your system and for how long...

 

[hemi=22s 10+ year member]

r u p[laying with car off or 2nd battery just to help out if not playing with car off use an isorelay 200 amp or just a in line fuse btwn 1 and 2 battery dont really need an isolator

def do big 3

n i plan on shipping that eclipse tomorrow lmk if u still wanna trade

what other add ons (electrical u have drawing current

also what is the current draw (amps) that swiss audio is pulling

 

[hemi=22s 10+ year member]

i have my extra BATTS OFF A STINGER ISORELAY 200AMPS THAT TURNS ON AND SUPPLIES CHARGING OFF THE STEREO REMOTE WIRE SO WHENEVER THE H/U IS ON ITS CHARGING THE 2/3 YELLOWTOPS

U DONT NEED A ISOLATOR OR ISORELAY JUST MIGHT WANNA PUT AN INLINE FUSE IN THE POWER

 

[rockmo 10+ year member]

yes hemi, i want to trade. will have you a tracking number on the alarm tomorrow.

the only stuff stereo wise is the headunit, amps, truck is a basic. no rear defrost, no power windows, or any of that jazz.

as for your going up alternator amperage i don't understand that question.

i just want to get the alternator rewound for higher amp (i.e. 140-160amps) soon if it is needed. thanks for the help guys, goin to get this thing together someday!

 

[hemi=22s 10+ year member]

hook it up the way u got in mind no isolator with 2 batts do ur big 3

and stick a mm on there and see how the voltage is doing if u are gettin severe drops then get the alternator rewound or buy a high amp

u might be able to use a different gm model that has fact high output

 

[rockmo 10+ year member]

k, where will i stick the meter? at amp or one of the batts?