Wiring/Power handling Questions

[bimmerboy 3]

I am planning my first real DIY build and have some questions regarding the wiring... Before I ask, here is my planned setup:

Power/Wiring

-Stock Battery

-Stock Alternator

-Big 3 upgrade to all 1/0 gauge wires

-300A Fuse

-12 gauge speaker wires for the subs

Sub/Amp

-Fi SSD 15" wired at 1ohm

-Audioque AQ1200D (1200rms@1ohm) (40A x3 fuses, 120A total) (4 gauge connectors)

1) Will doing the big 3 upgrade be sufficient enough for my battery and alternator for this system? If not, what else should I look in to?

2) Should I hook up the amp w/ 4 gauge wiring or use 1/0? I would prefer to use 1/0 but the connectors are 4, is there a solution to this? Is 4 gauge sufficient for this kind of amp?

3) Is the 300A fuse overkill since my system is only 120A? Should I get a 200A fuse?

4) Anything else i'm missing?

I def. want to get my install right the 1st time, so any insight would be appreciated. Thanks!

[CrazyKenKid 64]

1) doing the big 3 will HELP i would recommend getting a small battery to keep the voltage constant and get a voltmeter to monitor the voltage going into your amp!

2) 4 gauge wire can support 135amps of current and with 12 volt that is about 1620 rms so 4awg will support your amp well enough

although ideally if you want to use 1gauge you will need to buy a 1/0 reducer to 4awg like this device here

0 GAUGE to 4 GAUGE WIRE REDUCER :: WIRE GAUGE REDUCERS :: Installation Accessories (TOOLS) :: AUTOTOYS (scroll down)

3) what are you fusing with 300amp fuse? the alt to battery (part of the big 3) or the 4awg wire from front battery to rear amp?

4) volt meter and build log!

[CrazyKenKid 64]

3) i think you are refering to the 4awg gauge wire from front to back for that i would use a 120amp fuse

OR most ppl like to fuse to the amp! so if the amp has 120 of fusing on it just fuse to 120 amps

OR some ppl like to fuse to the wire capacity! so if you 4awg can support 135amps of current use a 120 amp fuse!

lol odd how 120amp fuse was in my example twice lol!

but of course if you use 1/0 wire you will want to use a bigger fuse as the wire has a higher capacity of current

(provided you are a guy who likes to fuse to the wires capacity)

[bimmerboy 3]

3) i think you are refering to the 4awg gauge wire from front to back for that i would use a 120amp fuse

OR most ppl like to fuse to the amp! so if the amp has 120 of fusing on it just fuse to 120 amps

OR some ppl like to fuse to the wire capacity! so if you 4awg can support 135amps of current use a 120 amp fuse!

lol odd how 120amp fuse was in my example twice lol!

but of course if you use 1/0 wire you will want to use a bigger fuse as the wire has a higher capacity of current

(provided you are a guy who likes to fuse to the wires capacity)

I was actually referring to the 1/0 alt to battery connection, I was going to fuse that at 300A b/c of the wires... I didn't even think of fusing the amp, should I? I thought the Amp has fuses already so I should be set?

Thanks for the advice!

So for my setup would 1/0 gauge wiring for the whole system help my battery/alt.? If so I will wire everything with 1/0

[CrazyKenKid 64]

o for the alt to battery use a 300 amp fuse and 1/0 wire! that way you aren't limiting the output voltage/ current from the alt to the battery by using to small of a fuse.

i recommend fusing the run of wire from the front to the amp b/c well what happens if something shorts out for some reason and the wire get over 135amps of current? well fi it does it gets hot and the jacket of the wiring heats up and then melts and starts a fire! then your car will burn down and insurance will lol at you b/c you didn't use a fuse and they will withdraw your calm!

fusing is for safety, and yes 1/0 will help out a lot! as it can carry more current then simple 4 awg should! and there is a guy selling 50ft of 1/0 kicker flat flex wire for 140 on this forum!

[KU40 173]

You can't just say stock alt and stock battery, you have to tell us what size they are. Quite a big difference between a stock 70 amp alternator on a honda civic and a 160 amp alternator on a truck.

You HAVE to fuse the wire from the battery to the amp within 12-18" from the battery. That fuse is in place to protect the wire, not the amp. If the wire between the battery and amp shorts out, you need a fuse there to blow and stop sending current otherwise your car will burn down.

[bimmerboy 3]

You can't just say stock alt and stock battery, you have to tell us what size they are. Quite a big difference between a stock 70 amp alternator on a honda civic and a 160 amp alternator on a truck.

You HAVE to fuse the wire from the battery to the amp within 12-18" from the battery. That fuse is in place to protect the wire, not the amp. If the wire between the battery and amp shorts out, you need a fuse there to blow and stop sending current otherwise your car will burn down.

Just Checked my car....

Alternator is 140A (stock Denso unit)

Batterry is a Duralast 130 reserve (idk what that means)

Would doing the big 3 be enough to prevent voltage issues?

I will fuse the wire going from the battery to the amp, why do you have to fuse it within 12-18" of the battery tho?

[The enD 467]

I will fuse the wire going from the battery to the amp, why do you have to fuse it within 12-18" of the battery tho?

Very good article , if you understand it after reading your question will be answered.

http://www.bcae1.com/fuses.htm

[KU40 173]

You can't just say stock alt and stock battery, you have to tell us what size they are. Quite a big difference between a stock 70 amp alternator on a honda civic and a 160 amp alternator on a truck.

You HAVE to fuse the wire from the battery to the amp within 12-18" from the battery. That fuse is in place to protect the wire, not the amp. If the wire between the battery and amp shorts out, you need a fuse there to blow and stop sending current otherwise your car will burn down.

Just Checked my car....

Alternator is 140A (stock Denso unit)

Batterry is a Duralast 130 reserve (idk what that means)

Would doing the big 3 be enough to prevent voltage issues?

I will fuse the wire going from the battery to the amp, why do you have to fuse it within 12-18" of the battery tho?

I'm not sure what's all in the link the end posted, I'll just go through some points here.

1) You want to protect the wire. The farther away from the battery you put the fuse, the more wire is unprotected to short out.

2) Where would you put the fuse from between 18" and your amp? The wire runs through your car. Are you going to fuse it somewhere in there under your carpet or door jam?

3) Remember that fuses protect wire AFTER the fuse, not before. If the fuse blows, any wire between the fuse and battery is still live.

Your alternator and battery look to be sufficient. I have two amps in my system, including a 1000+ watt sub amp, and have a 130 amp alternator and I have no dimming or voltage drop issues. I only use a 100 or 120 amp fuse, I forget. At any rate, it has never blown in 5+ years with basically the same amplifier power. You'd be fine with a 120 amp fuse.

[bimmerboy 3]

Thanks guys!

So just to be clear:

-0/1 gauge for the big 3 with a 300A fuse.

-0/1 gauge for the batt. to amp. but w/ a 120A fuse near the battery, then to 0->4 adapter at the end to input on the Amp(4gauge hookup).

sorry for so many questions, just wanna get everything right the 1st time!

[caintrain 0]

sorry for so many questions, just wanna get everything right the 1st time!

Being your first DIY build do not expect to get everything right the first time...that being said take your time on your install and maybe have someone with you that knows what they are doing to check you along the way and make sure you are doing the little things properly...are you building a box as well or getting one made for you?

[bimmerboy 3]

Being your first DIY build do not expect to get everything right the first time...that being said take your time on your install and maybe have someone with you that knows what they are doing to check you along the way and make sure you are doing the little things properly...are you building a box as well or getting one made for you?

I'm having one made by Andrew@ArgentAudio... Honestly I don't think it will be too bad, the hardest part for me will be running the wires through the car as well as hooking the stock Head Unit to the MTX re-Q(sound processor)

researching and learning on here has def. helped me out a shit load though.

Edited July 9, 2010 by bimmerboy