wire size for fuse size

i will be using 2 amps, i to power 4 subs and one to power my front speakers. the sub amp uses a total of 90 amps on the amp (3 - 30 amp fuses), and my speaker amp, is only 30 amps on the amp (2- 15 amp fuses). what wire size whould i use for the 2 amps, i can use a power disp block. but i was thinking a 8 gauge with a 40 amp fuse for the speaker amp, and  a 4 gauge with a 100 amp fuse for the sub amp, i do not mind running each amp there own power cable if needed. infact i prefer that. i also have a 1 frd cap that i will be hooking up to the sub amp also. and thoughts would be great. oh by the way, 0/1 gauge wire is hard to come by were im located.

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Trav

Click the "power and ground wire size" link to the left.  Remember that you fuse your power wire depending on the size of the wire and that the ground needs to be at least the same gauge.

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1/O AWG welding cable should be available in most areas.

ya ground cable is not an issue. but still the 0/1 gauge is still a bit hard to get, well to get in a reasonable price. they want to charge like $2.50 per foot for 1 gauge. i got lots of 4 gauge and 8 tho. thats y i was asking about the 4 gauge, if it would be good enough or not. and the power guide, is a great rule of thumb, but i want to know if someone has succesuflly pushed about 90 amps, and 30 more out of 4 gauge without any problems. i could get a 130 amp waffer fuse for 3 bucks, and use the disp block to sepperate the flow to the amps. i know that i can do 100 amp or so out of 4 gauge, but i dunno if it would do any damage, or if my wire will handle that kind of power. i added it all up, and it should be a grand total of 1250 watts (peak) about 625 watts (RMS), and 120 amps. running about 16' and according to that wire guide, i should use 2 gauge. but i was wondering if i could just use the 4 gauge for the sub amp, and the 8 gauge for the speaker amp. would that be a big problem, of just kinda anoying running 2 power wires to the battery. i know that i sould simplify things using only one power cable, and splitting it at the amp. but i was thinking that i could just run each amp there own power cable, would that be a good thing, or would that be a bad thing. thoughts????

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Trav

Use two 4-gauge wires together to be equivalent to 1 gauge.

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k that could work, but then im still running 2 wires through the fire wall, and my speaker amp only needs an 8 guage, and my sub amp requires 4. but my block is 3-4 awg in, and 4-8 awg out fused. and i have a nother, 2-1 awg in and 4-4 awg out un-fused. and 2-8 awg wires is about the same size as 4 awg. and that way i know for sure that i wont be under powering anything. now next big question. when doing the big 3, do i need to run bigger power wire from the alternator the exact same path to the battery. in my car, it goes from the alt-to the starter, then to the battery. or can i just jump it from the alt to the battery, and the ground from the engine block to the frame can be from any ware, to any ware right???? or does it have to be at the same ground points as factory put it. and the batt ground to ground is easy.

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Trav

"when doing the big 3, do i need to run bigger power wire from the alternator the exact same path to the battery. in my car, it goes from the alt-to the starter, then to the battery. or (1) can i just jump it from the alt to the battery, and the (2) ground from the engine block to the frame can be from any ware, to any ware right?"

(1) Yes, and (2) Use the same (or very near to) locations as OEM to prevent differences in potential.

 

 

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Build the box so that it performs well in the worst case scenario and, in return, it will reward you at all times.

1) thanks, 2) ya and thanks.

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Trav