Page 1 of 2 12 LastLast
Results 1 to 15 of 21

Thread: Does it matter what wire I use??

  1. #1
    zapcocruiser
    Guest

    Cool Does it matter what wire I use??

    In the world of car audio there seems to be some confusion between the Newbie's and Driveway installers about how to wire a car audio system correctly. Now when I say wiring I'm talking about everything from Power and ground to signal and fusing. I've even seen installs performed by some local stereo shops that are using the wrong size power wire (too small or multiple lengths butt connected together). Here are some good things to think about when you are planning to wire your system...

    Let's talk about power wire.......Before you go out and buy a bunch of cool looking BLUE power wire to use in your vehicle you may want to read this first....... try and figure out what size or Gauge wire you will need and how much of it.. There is an easy way to do this...

    First measure the vehicle... this will give you a ball park figure of how much (in Feet) of the wire you will need (example 18 feet). It's always a good idea to give your self a few extra feet (remember.. no butt connecting a bunch of wires together, that can cause fires) .......

    Second take a look at the amplifiers you will be using and see what size fuse (or fuses) they have on them, if you don't have all of them yet see if you can find out what size fuses are on the ones you will be getting (it's important to be accurate). After you find out all the fuse values add them all together and you'll come up with a number. (example... AMP #1 has two 25amp fuses and AMP #2 has one 40 amp fuse.. add them together and you come up with 90amps of fusing) That number is going to be used in two places..

    The first place that this number is helpful is when you are trying to figure out what size fuse you will need under the hood within 18 inches of the battery. A good rule of thumb is to have no more than 5 or 10 amps of fusing more than what your amplifiers require (example... if your total amp fusing is 90 amps, the fuse under the hood shouldn't be more than a 100amp fuse under the hood within 18 inches of the battery). Try to make your under the hood fuse as close to your total system amperage as possible without going under it. Why do you need to have a fuse under the hood... well It's simple... To protect your battery and the run of wire from shorting... If there is a short in the line, the fuse will blow instead of shorting straight to the battery and vice versa helping to prevent a nasty little fire and melted wire.

    The Second place you will use this number will be to determine what Gauge wire you will need to run from the Battery to the amp rack location. Regardless of what you may have heard from your friend or what you may have seen in someone else's vehicle, not all size power wire is the same... You should NEVER splice your power wire or use multiple lengths of wire butt connected together. This does nothing more than offer more resistance and reduce the overall voltage but more importantly it's a FIRE hazard. You should always have solid runs of wire (this includes speaker wires and interconnects) from point A to point B.


    Now that you have the length of wire you will need (example...18 feet) and you have the total system fusing value (example... 90 amps) how do you figure out what Gauge wire you will need. I have included a simple chart directly from the IASCA Rule book below to follow. Using this chart...locate the total amperage of your system, in our example we have a total amperage of 90 amps. Then locate the number of feet you will be running (18 feet). Then look to the left on the chart and it will tell you how big or what gauge wire to use. For our example we can use 18 feet of 4 gauge wire to run from the battery to the amp rack. You should then separate the wire using a distribution block. Using the FUSE values on each amplifier you can then use the chart to figure out how much and what size wire you can use from the distribution block to each amp. At this point most people tend to use 8 gauge wire from the distribution block to each amp for smaller amps and bigger wire for higher fusing values accordingly.

    The chart show the MAXIMUM number of feet you can use of any given wire size. You should not run wire longer than the recommended maximum length indicated on the chart. You can however use less.. (example.... The chart says you can use a maximum of 18 feet of 8 gauge wire for 40 amps of fusing... you only need 4. You can just use 4 feet of 8 gauge wire.)


    Think of power like water and the wire you use like the pipe the water uses to get to you.....The smaller diameter pipe you have the less water will flow to where you want it. Your amplifiers need to have as much power to them at all times of operation as you can give them. If you limit the amount of voltage or power they can use by using smaller gauge wire than recommended, they will not be able to give you the performance they should.

    It is also a good rule of thumb to use the same size Ground wire as the wire going into your amp for power....(example.... You have 4 gauge wire going into your amp for power... you should use 4 gauge wire for the ground/Negative connection) When attaching the ground or negative wires from your amplifier to your vehicle you should always use some sort of ring terminal... if not for anything else because it looks neater than a bunch of wires twisted around a bolt. You should also sand or scuff the area where the bolt will be attached to the vehicle with sand paper to expose bare metal for a good contact. You can always spray a little primer to cover the bare metal. You should always use a ring terminal for the correct size wire you are using for the Battery connection as well... cutting down a 4 gauge wire to fit in a smaller gauge ring terminal is like putting a 2 inch fitting at the end of a 5 inch pipe.... It's just not going to work.

    When ever Wire passes through a panel (the fire wall) you should protect the wire with some sort of grommet. This will protect the wire from chafing and shorting out.

    After running all of your wires to where ever they may end up going you should trim off any excess wire that may be left over.. and wire tie them neatly. It'll look neater and will help to eliminate noise in some systems.

    Remember... you spent all the hard earned money to make your truck look Phat... Don't Ghetto the system!
    :bigthumb: :bigthumb: :bigthumb: :bigthumb: :bigthumb:
    Attached Images Attached Images
    • File Type: jpg 1.jpg (79.9 KB, 512 views)

  2. #2
    The ONE and The ONLY BlazinBlue's Avatar
    Join Date
    Oct 2001
    Location
    Broken Arrow,OK
    Posts
    1,585
    I have always used 2 or 4 gauge for my power and ground. All I know is not to get different sizes for the two. But I also have only had a 300 about a year and traded for a 500 for half a year in my car. Both hit good. Both were used on a RF 15 and when I swaped it for 2 12s. But I got a 800 watt amp b4 my blaze died, I pounded those 12s like a mofo and I still only had 4 gauge wire. Now I gunna hook it up 2 my new 15s till I get a bigger amp again.:smoker:
    Tulsa Chaper VP - Vertically Challenged
    :smoker: - 1989 S10 Blazer 2dr - 1995 F/S 4x4 -:smoker:

    BLAZINLOW MEMBER #11

  3. #3
    Senior Bember blaze91's Avatar
    Join Date
    Jun 2002
    Location
    Ohio
    Posts
    1,327
    i always go overkill with wire. grounding both battery and amps to frame. and running new cable from alternator to batt.
    4500 hp 392 TBI
    14" Foose "Spank 5's"
    Shaved windshield mod
    124 pump hydro setup with 7-link
    Blue paint finally

  4. #4
    zapcocruiser
    Guest
    That's not over kill.. that is exactly what you should do when installing a system with a large current draw..

  5. #5
    woo!! dancey dancey!! Boink's Avatar
    Join Date
    Oct 2001
    Location
    Streator Illinois
    Posts
    4,018
    I got a regular battery going to a sintger dry cell 1000 series i think. from that (about 2 feet of wire) to distribution block. :D i rock!
    Im2Drunk2C: well bro i gotta run, work time
    Im2Drunk2C: later
    B o I k 2 0: alright
    B o I k 2 0: before you go tho
    B o I k 2 0: I love you
    Im2Drunk2C: awwww
    Im2Drunk2C: <3

  6. #6
    Registered User
    Join Date
    Sep 2002
    Location
    Billerica, MA
    Posts
    14
    A professional installer set up my system with 8 gauge wire to a 500/1 amp powering 2 jlw3's. I took it back today and they're gonna switch it with 4 gauge ground and power next monday. Thanks for the post, hopefully my amp will quit shutting off now :)

  7. #7
    zapcocruiser
    Guest
    A professional installer set up my system with 8 gauge wire to a 500/1 amp powering 2 jlw3's. I took it back today and they're gonna switch it with 4 gauge ground and power next monday. Thanks for the post, hopefully my amp will quit shutting off now
    I would have smacked that guy in the head... It's installers like these that get to me... How can you call yourself a PROFESSIONAL and do someone wrong like that.... I hope your aren't paying for the new wireing.... With an amp like the 500/1 He should have used the 4 awg wire in the first place. Oh ya.. Make sure that he upgrades the Ground wire as well.

  8. #8
    Dark Side Master LayinBodyBlazer's Avatar
    Join Date
    Apr 2002
    Location
    Ledbetter, KY
    Posts
    4,512
    good post Ryan :)

    I go over kill myself, nothing like 8 guage subwoofer wire :D

    Team Rockford Fosgate Member
    My Street Source Mag Page
    My MySpace Page

  9. #9
    Off Road Member mcgrath609's Avatar
    Join Date
    Sep 2003
    Location
    Ohio
    Posts
    502
    Speakin of local dealers that install things, my friend took his to a local shop, and they ran 8 guage wire, now that isn't bad n till they ran it right beside the headers and thru the fire wall, and it kept shorting out and blowing fuses, but they should have used 4 b/c he's runnnin 800watt of RF to 2 RF Punch Hx2's(or something real close to that of the subs!
    95;Eagle Talon TSi AWD
    94; S-10



    Still blazin'

  10. #10
    Registered User
    Join Date
    Sep 2003
    Location
    Shelton,CT
    Posts
    3
    It depends on how much watts your going too go like anyhting over 2000 watts you would go from a zero gage wire then split it into a four gage.

  11. #11
    Beer,Its whats for dinner Paraquat's Avatar
    Join Date
    Feb 2002
    Location
    Connecticut
    Posts
    2,057
    watts = amps * volts
    once you have that you solve for a 2000 watt stereo at 12 voltsDC to get amps, and then look that up the amps vs. feet chart to find out recommended wire size.


    --Steve
    I hate my truck.

  12. #12
    Dark Side Master LayinBodyBlazer's Avatar
    Join Date
    Apr 2002
    Location
    Ledbetter, KY
    Posts
    4,512
    lol 4 guage handling the amperage of a 2000WRMS draw; better keep a fire extinguisher handy

    Team Rockford Fosgate Member
    My Street Source Mag Page
    My MySpace Page

  13. #13
    Senior Member bigjsp's Avatar
    Join Date
    Nov 2002
    Location
    Columbus, OH
    Posts
    12,665
    Originally posted by SoLoudItHtz
    lol 4 guage handling the amperage of a 2000WRMS draw; better keep a fire extinguisher handy

    2000 / 12 = 167A

    per the chart, 4 gauge at 167A should be good for up to 10 ft at only a 0.5 volt drop. Not quite fire extinguisher time.

  14. #14
    Dark Side Master LayinBodyBlazer's Avatar
    Join Date
    Apr 2002
    Location
    Ledbetter, KY
    Posts
    4,512
    hehe charts don't lie but then you have variables that come into play like insulation material and thickness as well as cable material

    ;)

    honestly, I wouldnt trust running that much on 4 guage :D maybe thats just me though

    Team Rockford Fosgate Member
    My Street Source Mag Page
    My MySpace Page

  15. #15
    Senior Member bigjsp's Avatar
    Join Date
    Nov 2002
    Location
    Columbus, OH
    Posts
    12,665
    Agreed. I use #2 welding for everything. But I bought a 100 ft spool of Blue and a 100 foot of black for $20 each at a Farm and Fleet store going out of business sale so its more economics than engineering.

Posting Permissions

  • You may not post new threads
  • You may not post replies
  • You may not post attachments
  • You may not edit your posts
  •