Fuse and wire gauge size for whole system

[GSG2Teg]

So, I know there are posts out there already about what size of fuse and wire sizes to use, I'm kind of looking for someone to double check my math and info so I don't blow something or burn my car down, and see if I still have the power from the wire currently installed. My plan in the next couple of months is to install a third amplifier for the subs and install a fuse for my main power wire running back to a fused distribution point I have already installed. In a round about way I kind of forgot to install one up by the battery.

Like I said I already have a fused distribution point probably within' a foot of the amps already installed so I'm not too worried about wire size and fusing at this location. My car is a 1990 Acura Integra and I have my amps installed where the back seats are located, so I'm thinking the main power run is probably 10-12ft max, if that, and is a true 4 gauge. I currently have two Alpine MRV-F340's installed and fused at the recommended 30 amps each. The third amplifier I'm looking into would be a Pioneer GM-D8604 and would require an 80 amp fuse. So, by what I read online, doing all the math and looking at the charts...I'm think my main power wire gauge will be fine for what I am doing.?

As for fusing the main power wire up near the battery I think I'm looking for a 150 amp fuse? I think the math comes out to roughly 140 amps. My other question is wire and fuse ratings. Will my wire handle it and what are the recommended max fuse ratings on a specific wire gauge? Is it safe to go off the chart that Crutchfield has? I think I should be fine with a 150 amp fuse on a 4 gauge wire, and to make all this simple would be to install an inline fuse holder and call it good but I'm kind of **** and like having options or extra ports if I need it. I started thinking about taking all the wires off my battery, installing a fuse, a distribution point and connecting my car, and stereo (amplifiers) all in one up near the battery.

I've been looking into "The Big 3" but all I seem to find is people using 0 gauge wire and to me that seems way to excessive for most applications out there. I've upped my starter wire to what is labeled as a 4 gauge wire but when making connections I'm finding out its probably a 6 gauge which is fine with me, it's a little bigger than what was on there. I'll most likely be leaving the starter connected to the battery, as it is not fused. I'll probably be upgrading my alternator wire as well but haven't decided on what to run yet. I have a bunch of this "4 gauge" (actually 6) that I'm thinking of using or just going out and getting more 4 gauge. Any thoughts would be helpful. I thought I should upgrade it but I don't think it needs to be 0 AWG.

But back to the fusing, if I add this "70 amp Battery Fuse" for my car onto the distribution block for the amps would I just be adding the amps together? (140 + 70 = 210) So, basically getting an ANL fuse holder with a ~210 fuse and installing it prior to the new distribution point? And now back to the wire rating..would it be safe to do on a 4 gauge wire or shall I up it to a 0 gauge for that foot or so that I'm running? If I upgrade that foot of power wire, should I upgrade my foot or so of ground wire as well since it's only the true 4 gauge or stay with whatever size I'm using as a charge wire from the alternator?

Sorry for this being so long. I'm kind of newb when it comes to large electrical.

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[wew lad 5,000+ posts]

pull the 4 gauge out, and cut it to use for your amplifier ground and power runs to the distro and grounding points

buy 12ft of 0 gauge ofc welding cable, and a distribution block that will accommodate it with multiple outputs (2 8 gauge, you only need 8 gauge for those small 30 amp loads and 1 4 gauge for your new amp)

put a 200-300a fuse on the 0 gauge welding cable, ideally 200a, and then put fuses in your distro block matching the amps fusing.

ive been where you're at before with multiple amps, this is the best looking and cleanest way to do it imo

 

[GSG2Teg]

I think I get what you are saying. I am currently using an older Streetwires bus fuse style distribution block in the back. 4 - neg. and 4 - positive outs. I believe it can handle 0 gauge in, and 4 out. I am currently using 8 gauge with the 30 amp fuses for the tiny Alpine amplifiers at this location. Like you said they are a smaller load. I was hoping to get away with the 4 gauge run, add an anl fuse and distribution point up front and at most add 0 gauge from the battery to the new/upfront distributor. I might just do a full 0 gauge run, add a 250 ANL first, a new distribution point for "car fuse box" (it's already fused at 70) and for the amp run in the back(140), then have the distribution point in the back for the amps. I probably should say the new distribution point will most likely be a 4-port MANL style (150 for amp run if I can get away with it, and 70 for car). And thank you on the suggestion for the new amp gauge.