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What type of wiring should I get?

2079 Views 23 Replies 5 Participants Last post by  alanthing
I pulled out my sub and amp a few months ago since my car's been in and out of the shop. After I invest in a good alarm, I want to put a Mac mini in my car do all that fabrication stuff myself. Looks like fun. Anyway, I want to put my sub back in and it'll be a while before I get the rest of the components put in, but I want to go ahead and run the correct power wires.

I have an Alpine MRD-M301 for my sub and will be getting some sort of 4-channel amp later for my speakers (Alpine MRV-F345 maybe?) at around 75w RMS x4 (wallet willing). I'll also need to power the Mac mini via CarNetix CNX-P1900 which can handle 140w, but I doubt it'll get that high because it's also designed for Pentium 4s, which the mini is much cooler than. Lastely, the monitor, but that's only around 9w, so I'll just splice into the cigarette lighter wire.

Whew, okay, so should I get a 4-gauge kit (like this?) If so, how would I get power to the computer? Looking at, I saw an install where someone put an 8-gauge wire straight from the battery to the computer power supply, but 8-gauge seems pretty big for 140w (realistically, 60-80w).

Lots of planning to do... thanks for the help!
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yeah I would get whatever the manual recommends, if it can take 4 gauge get 4 gauge and so forth...
Always go bigger if you want, less to do later if you want to upgrade.

Beleive me i'm running a 0awg main power wire to a d-block where i have 2 4awg splits. 1 4awg runs to a 4ch amp ran active, 82rmsx4 @ 4ohms, and the other 500rms [email protected] each ch on my 4ch amp is ran at 8ohms, so i'm getting something like 40rms [email protected]k my Power wire is big enough for the amount of power i'm running?

Can't ever go big enough, but you can go too small......and if you go too small, you'll have some problems.

I'd say go straight for some 0awg, get a d-block and then run some 4awg to each amp. That would be the most efficient choice for me, and the most room to upgrade in the future.....Just make sure your main power wire is fused right.

Not exactly sure about this but if you wanted to run your sub amp for awhile before you put your 4ch in, simply connect only 1 of your 4awg's to the d-block and power up the sub amp, you won't loose any power only using 1/2 of your d-block, because the amp is pulling the current, not the d-block.
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I'm hoping to get some sort of kit that has everything I need. 0awg sounds like overkill. It seems like a need two 8 gauge connections (one for each amp) and a 10 gauge for the computer. Would that be a 2 gauge wire? Where can I find a d-block like that (8x3 or 8x2+10x1)? Thanks!
^^ for your setup a 4 gauge would be perfect, you can get a distribution block and split the 4 gauge into 8 gauges and 10 gauges. 2 gauge is kinda rare wire I would go with like either 4 gauge or 0, although 4 is my choice
There is never overkill for wiring, If you decide to upgrade in the future, why pull out existing power wire to run new power wire, do it right the first time, anyone that plans for the future will tell you that.

I think 0 -4 awg would be the right thing to do, but i'm not making choices here, i've already done it.

Check out or for wiring and accessories.
Think of your wires as straws the smaller the wire gauge the smaller the straw. think of the 12 or 16 gauge as a coffee stirrer and 4 gauge as a big like mcdonalds straw. which is easier for you to drink a milkshake with?

Personally I would run 4 gauge to a D-block and then 8 from the block to that amp. and later you can always add in a a sub amp and not hafta re-wire. Though I'd pre run RCA's for the second amp and just tuck them away until i got it. even if you dont want a sub you might decide later on to get on and all the labor will be is just connecting a few wiresnot having to pull any
Thanks for responses, guys. Goldenchild, sounds like 4 gauge will be enough for me. I guess I had in my head that 4 gauge was just the size of 8 gauge x2. But, if you think I'll be able to run 8/8/10 gauge wiring off of the one 4 gauge, then I'll start looking toward that route.

I'll probably be back soon asking the best ways to run the wire, but I have to figure out where this computer is gonna go first. I'm thinking center console arm rest... but we'll see...
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might as well just get 4 gauge, and use a D-Block that goes from single 4 ga to 2 4 ga then get two 4 ga to a double 8 ga if that doesnt make since lemme know i'll try to clarify it some more
I've decided on a block that does 1 4-gauge in and 4 8-gauge outs. I decided on a less-powerful four-channel amp.

I have a question about fuses. Where should they be? If I have one near the battery on the 4-gauge main cable, do I still need them on each 8-gauge cable out the block? If so, why? The amps has (a) fuse/s directly on them. So I guess I'm asking, where do I need to have fuses (without going over kill)?

You need a single fuse (i would suggest 60-100amp) within roughly 18" of the battery...thats all you will need. I included a pic of my fuse and wiring. Make sure you zip tie it down to something, as you don't want to fuse flopping around. You do not need fuses after the distribution block, it's unneccesary. I run a 4 guage wire to a 4-8 AWG distribution this i run a 600 rms alpine sub amp and will be running a 40 rms x 4 amp for speakers. If you have quality wire, splitting 4 guage to a couple of 8 guages is plenty big for a setup like mine.

Hope this helps

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Also you asked about routing the wire, many on this site run through the passenger side, but i like running it down the side with the battery. This is a picture of me lying on my back looking up through the pedals to the big grommet where i ran my power wire through, hopefully it helps you figure out a spot to run it. I also ran my alarm wiring through it, so there is plenty of room. A little vaseline or grease will help you get the wire through if you are having trouble, just make sure to wipe it off before you apply 12Volts to it.


Edit: The blurry thing in the front of the pic is the steering column, just for reference
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The hole you've got your wiring through: you just cut one of the "nipples" off to make that right? I had my original wire going thru to the passenger side and I pushed the nipple in and couldn't get it out (big hands and fingers
) so I just put the wire to the side of it (bad idea, which is why I pulled it out).

I like the look of the engine with the power wire running on the driver's side, but I want to have both of my amps on the passenger side. Where's your dist block? The driver's side is only going to have my computer and a fan probably, so I'd have to run more power wires across the trunk.

Thanks for the pictures, by the way. I'm a visual person and it's helps.

Another question, still on topic though: When adding a 4-channel amp, I'm sure it helps to run new speaker wire. I've read all about EMI and when signal wires come near power wires they should be at a 90 degree angle. Does this apply only for RCA patch cables, or anything carrying an audio signal? My limited knowledge of electronics tells me that the new speaker wire would be carrying more of a power signal that an audio signal, and would be less susceptible to EMI than RCA. But, I'm just guessing. If the speaker wires would be just as prone to EMI as the patch cables, how would you get those wires up to the speakers (if I'm running the main power cable on the passenger side) on the passenger side without getting crazy EMI?

EddieMoney, you've been answering tons of questions for me lately. THANKS!!!!!!!
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I just took an exacto knife and slit a little hole in the rubber, i didn't cut anything off. Then the little plastic cover on the battery post I used some scissors to cut a hole in the side of it. I have huge hands/fingers too (im 6'3 235) but I was able to get it without too much issue on the drivers side. My amps are both on the passenger side. I run the wire down the drivers side, then across behind the backseat to my amp box where the distribution block resides. If you look at my pic the front hole in the amp box is to adjust the distribution block without any issues.

The EMI applies to any power/signal wires including RCAs. I am in the process of getting new speaker wire run to all my interior speakers, it will be worth it in the end. If you keep the speaker wire and RCAs as far away from power and ground as possible you will be fine. When they do cross make sure you have some sort of barrier between them, i like using rubber tubing. I have never had a noise problem with slight overlap, just make sure the wires dont rest on eachother for very long.

No problem answering the questions, thats what this is all about, i like sharing my knowledge and experience.
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Would something like this (link) fit on a tC battery? Looks pretty nice...
Sure, but that is kind of a hassle. You would have to cut all of the factory power cables and hook them up to the stinger battery terminal block as well. This piece will not work in conjuction with the factory battery terminal. You would be better off with just a ring terminal around the factory bolt(pull the red cap off and you will see what i mean)
Oh, I didn't know it required cutting the other wires. Yeah, not worth the hassle. I had a ring terminal on it before, but I could never get it to stay crimped on. I've since found those ring connectors that tighten with a hex-screw, so I'll just try those. Thanks again
Try this, you will need a friend to help.

1. Grab a blow torch
2. Melt solder in the end of the ring terminal(make sure you are holding the ring terminal with pliers, you dont want to burn your hand)
3. Put a piece of heat shrink on the wire, and then strip the end of the wire 3/8" or so
4. Remelt sodler in the ring terminal with the blowtorch and shove the bare wire into it while crimping down the ring terminal at the same time
5. Heat the shrink tubing around your new joint
You will have a crimp and a solder joint and shouldn't have any trouble with it pulling out.

Hope this helps

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Whoa... I've never used a blow torch before. Sounds like a pretty tight connection though. Question: How exactly do you crimp a 8+ gauge connection? I've never been able to find a crimper (online or store) that does anything higher than 10. On my 8-gauge setups in the past, I've used the 10-gauge crimper and used heat shrink and stayed away from it because I've had that fall off before.
I just use the 2.99 crimper you can get anywhere and i have crimped all the way up to 4 guage with it. Just line the pointy part of the crimper up with the split in the ring terminal end and it will be fine. It will bend the two tabs in just fine. If you had heat shrink fall off you aren't doing it right, just be sure not to heat the tubing up too much. Just slow, gentle heat is ample. Also, try to avoid heating anything except the terminal, dont put the flame right on it, you just need the heat.
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