Wire gauge ?
Wire gauge ? I am doing the now we're you pull every thing into the car fuse box and all and i will be extending for the head lights amd things after but two questions one can i use 18 gauge for everything except the radiator fan wires or is 18 to small? And two were would i need to ground foe the headlights and things when I extend them I assume as possible to the head lights on either side as I can but correct me if I'm wrong.
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Joined: Dec 2017
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From: Bossier City, Louisiana
I'd be more comfortable with 14 or 16 gauge for headlights to minimize the voltage drops and poor illumination. As long as your radiator core support has a solid ground, you could ground there but I'd check the resistance first to be sure of a solid, low resistance ground.
Rick
Rick
I'd be more comfortable with 14 or 16 gauge for headlights to minimize the voltage drops and poor illumination. As long as your radiator core support has a solid ground, you could ground there but I'd check the resistance first to be sure of a solid, low resistance ground.
Rick
Rick
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Joined: Dec 2017
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From: Bossier City, Louisiana
I cannot say if 18 gauge is sufficient for everything inside your car because I have no idea what you are running (big stereo?) inside your car. It's all about the amps, voltage drop and wattage consumed. There are tables on the Internet for wire gauge size versus current and I think you need to get an idea of what the major things you are running consume for amps to answer your question safely.
Rick
Rick
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Your post is almost impossible to read and figure out what you're doing, but... 18 is prob too big for some things; sensors and such, with low signal levels. You'll end up with a gigantic blob of wire that won't behave. It's also too small for anything that draws more than just acoupla amps. Headlights, starter solenoid, battery feed into the cabin, blower motor, rad fan, and so forth. Those things need 12, or some even 10, to work right and keep from burning up. On both the 12V side and the ground side: the same current flows in both the red and the black wires.
Don't hallucinate that you can buy one reel of wire and hook up an entire car with it.
My advice would be, if you have that little knowledge of how to do wiring, don't try to do it yourself. Go find somebody with auto electrical knowledge and a stock of parts & materials, and pay them to teach you. Maybe have them do yours, and sit and watch them. Otherwise you're likely to end up with a basket case.
Don't hallucinate that you can buy one reel of wire and hook up an entire car with it.
My advice would be, if you have that little knowledge of how to do wiring, don't try to do it yourself. Go find somebody with auto electrical knowledge and a stock of parts & materials, and pay them to teach you. Maybe have them do yours, and sit and watch them. Otherwise you're likely to end up with a basket case.
Your post is almost impossible to read and figure out what you're doing, but... 18 is prob too big for some things; sensors and such, with low signal levels. You'll end up with a gigantic blob of wire that won't behave. It's also too small for anything that draws more than just acoupla amps. Headlights, starter solenoid, battery feed into the cabin, blower motor, rad fan, and so forth. Those things need 12, or some even 10, to work right and keep from burning up. On both the 12V side and the ground side: the same current flows in both the red and the black wires.
Don't hallucinate that you can buy one reel of wire and hook up an entire car with it.
My advice would be, if you have that little knowledge of how to do wiring, don't try to do it yourself. Go find somebody with auto electrical knowledge and a stock of parts & materials, and pay them to teach you. Maybe have them do yours, and sit and watch them. Otherwise you're likely to end up with a basket case.
Don't hallucinate that you can buy one reel of wire and hook up an entire car with it.
My advice would be, if you have that little knowledge of how to do wiring, don't try to do it yourself. Go find somebody with auto electrical knowledge and a stock of parts & materials, and pay them to teach you. Maybe have them do yours, and sit and watch them. Otherwise you're likely to end up with a basket case.
I am going off this thread and there saying use 18awg except the fans and head lights. My ac and stuff is gone as well as abs tcs and cruise control.
18 gauge would be okay for some parts. As mentioned previously sensors and the like. Anything that's going to draw anything over a few amps I would upgrade the wiring to 14 or 16. Resistance increases as the length of the wire does, so you need bigger wire to carry more amperage. The fans I would run 14 ga, things like the headlights should be okay at around 16. The nice thing about wire is that going bigger doesn't hurt, it just leaves you with a really fat harness.
That being said, I'm with RBO4Av. If you don't have much experience doing any sort of electrical work, especially on cars and 12v systems, I would steer clear. There is great potential to screw something up and leave you with a brick on wheels.
That being said, I'm with RBO4Av. If you don't have much experience doing any sort of electrical work, especially on cars and 12v systems, I would steer clear. There is great potential to screw something up and leave you with a brick on wheels.
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Teching In
Joined: Mar 2014
Posts: 38
Likes: 1
From: Paris, KY
Hello,
The word you're looking for is "ampacity". A wire of a specific gauge is rated to carry a certain amount of current over a certain amount of distance. If you want to run that same amount of current over a longer distance you might have to make the wire larger. That's where the ampacity charts come in handy.
If you are splicing the PCM or BCM harness and you are not making the wires much longer than stock, the stock wire gauge is probably fine. If you are looking to make the harness wires significantly longer, then the wire needs to be a lower gauge number (thicker). I would be cautious about making the sensor wires much longer than stock. My experience with GM's TBI and TPI harnesses is that they have been too long for every swap I've done. I haven't worked on my factory LS harness yet but I suspect I'll mostly be shortening the wires.
There are plenty of automotive wiring ampacity charts. Here's one:
http://info.waytekwire.com/blog/auto...e-gauge-guide/
The word you're looking for is "ampacity". A wire of a specific gauge is rated to carry a certain amount of current over a certain amount of distance. If you want to run that same amount of current over a longer distance you might have to make the wire larger. That's where the ampacity charts come in handy.
If you are splicing the PCM or BCM harness and you are not making the wires much longer than stock, the stock wire gauge is probably fine. If you are looking to make the harness wires significantly longer, then the wire needs to be a lower gauge number (thicker). I would be cautious about making the sensor wires much longer than stock. My experience with GM's TBI and TPI harnesses is that they have been too long for every swap I've done. I haven't worked on my factory LS harness yet but I suspect I'll mostly be shortening the wires.
There are plenty of automotive wiring ampacity charts. Here's one:
http://info.waytekwire.com/blog/auto...e-gauge-guide/
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Literally all I am doing is extending what went through the firewall on the drivers side by maybe 2 feet to install the fuse box behind the clove box. Pcm trans wires fuel injectors and such are same length they will be pulled through the a.c. delete panel. The ? Is the harness on the driver side when cut in half will 18awg be good enough for reconnecting the wires back together under the dash. As for the head lights and radiator fans I will be making them bigger I just need to know about the main harness if 18awg is sufficient to reconnect it back together for about 2 feet of extension. Or is there thicker wire then 18awg in there I see a pink wire there which is thick but don't see a gauge on it.