Nice use of snakeskin.
I'd recommend a grommet on the pass-throughs that don't have the radiused edges. Even with the chafe wrap, they will wear in with time.
Would be a good time to run any audio or data wires in a shielded parallel chase.
This looks more tight then some of the Toyota's come delivered from factory, nice job man! One more tip but maybe you already had this idea. Where the cable bundle comes through metal holes, especially the one cut out in the second pic. Put some extra rubber around the cable there or rtv, or else the metal will eat through the cables.
Holy crap! Only thing I see is you may want to shove a rubber grommet on the hole in picture 2. It's surprising how fast those edges can eat though looms.
I really wish I could fixate on a project like this. The best I can do is get everything in loom not wrapped up like this.
Just out of curiosity, why wrap/twist the wire like that? Doesn’t that mean you have to run a lot more wire since some of the length is used up in twists? Also tracing/repairing would be a nightmare I would think.
Why not run the strands together and use a sheath to add strength and protection?
My brother and I have enjoyed content from a company called HP Academy that have courses on different aspects of motorsports, typically racing focused. They go into the wiring techniques that they use, and I've followed along. It does make adding wiring more difficult. But I have not shown that each wire will have a heat shrink label on it that indicates it's use. So instead of wondering what the white wire with red stripe does, it will just have a label on it that says what it does, and a matching label on the other end of the same wire.
We don't do it this way in aerospace. Pretty much everything is twisted pair and straight bundled on a jig board so that the completed harness has "memory" of the shape and drops in place easily. Individual wire labels and colors just make assembling the harness more tedious, stocking parts more difficult, and inspection impossible. Connectors are labeled on both sides with the name of the assembly, the specific connector of the assembly, and the signal name. We use white for everything because it's easy to tell when its been charred.
If there's a problem with the harness you'll have to hack into it to fix it anyway so you can just use a multimeter to find where the broken wire goes.
No we don’t, in aerospace we twist and braid most of our harnesses. I worked on F15, F18, V22, CH47, AH6, AH64, 737, 747 and a handful of other commercial and defense aircraft. I’d say at least 90% of our harnesses were twisted for flexibility and also gave rigidity to branches and locations whether using tape and braid or string ties.
Only canbus needs to be twisted pair on automotive so it tends to be moot to do that for the entire harness. They are an absolute bitch to splice into this way and keep looking nice though.
Twisted pair is great for just about anything. Having an insensitive aggressor signal like a solenoid or motor on twisted pair decreases the size of its magnetic field further shielding data lines in the same bundle. It also lets you bus your grounds to a single junction instead of having to diagnose bad chassis grounds.
As a person who has made professional wiring harnesses for aircraft, the reason we twisted and made different types of braids etc, was for rigidity in certain areas and flexibility in others.
I love HP Academy, and I have several of their books. I will have to look up the wiring that this is centered around.
My concern for you is that this is a personal project car and that serviceability and simplicity would go a long way — you aren’t a Motorsport team with deep pockets that can just replace things wholesale if they go bad (are you?).
Based on my own personal experiences with project cars, simplicity certainly has its place. But maybe that’s just my anxiety talking and there’s nothing to worry about.
The benefits to true concentric twist wiring are that it’s sealed end-to-end and that the twist allows inherent strain relief along the whole run. You are correct about the weight and lack of serviceability, but typically this style of harness is made with aerospace connectors, tefzel (MIL-22759) wire, are sheathed in RayChem DR-25, and have epoxy in every breakout. They are not made to be serviced, instead just completely replaced from bulkhead to bulkhead.
Agree may have advantages is some advanced applications but no that I can think of in a car. I have made a few wiring harnesses and would not suggest this
Very very clean i like it alot, my only gripe would be if one of those inner looped wires ever needs replaced its gonna be bitch, unless I'm overlooking something that it wouldn't be?
You are absolutely right. By the time I'm done with this project I'll have a beautiful concentric wiring harness, with a rats nest of addons bundled with it! :D
Tach and speedometer signals should be fine, those are just a pulse. High speed data, and audio signals can develop noise, and cause weird issues.
Also, and I cannot stress this enough, grounds are the most important part of a good harness. Outside of that looks like you are doing a fantastic job.
I am installing a fitech fuel injection system onto a jeep YJ. they stress that the tach wire should not be next to any other “frequency” wire, like a motor. The induction created by winding the wires is a real possibility apparently.
Other than that, it looks great!
Really? Well, today I learned. I have always seen that the data wires are affected by induction the worst, and that's why they are a twisted pair in the harness. Doesn't help that most of my formal training was long after speedometer and tach went to data stream instead of pulse drive. I suppose it makes a difference on the pulse drivers if they are pull high, or pull low as to how they respond to unwanted AC current.
The tach and speedo are the ones creating the noise.
Mainly because they use a magnetically induced charge(this creates the ac current that then bleeds into every other circuit in the harness. 5v sig is the worst effected by it.)
Thanks for the clarification. I mostly skipped over these problems in my build, The audio sub-harness is actually isolated (by the width of the cabin) from the main harness, and my '86 resto-mod does not have any data wires.
Still, good info if I ever get my next project off the ground, it'll be new enough for data integrity to be a concern.
Thank you! I never knew until my recent dive into wiring how important grounds are. I don't have those completely clear in my head, so hoping to get some feedback on how and where to put those in.
Clean, threaded metal, star washers, and covered in dielectric grease. Try to avoid self tapping onto sheet metal wherever practical, and ground all major assembles. Run a ground strap from engine to chassis, and from chassis to body (if applicable). Also, run a dedicated ground from the dash frame to the body panels. When using threaded holes clean them with a thread chaser, and use a new bolt.
Also, there is no such thing a too big a ground. I only used 3 wire sized in my build, 16, 10, and 2. I have a 2 gauge wire fender to block on both sides of the engine bay, and a braided ground from the firewall at the wiper motor to the block. My winch ground shares a stud with the passengers side fender ground stud, and is connected to the primary battery. My amps and inverter are grounded to the rear seat belt capture nuts (did a rear seat delete), and the dash and engine harnesses have a 10 gauge wire running side to side, grounded on both ends, with several junctions in between where the assorted 16 gauge grounds combine to the main ground path.
Hey u/Material-Job-1928 would you mind explaining the comment on signal wiring more?
The reason I ask is because I recently had a four-month long problem with my engine coolant sensor. One day my temperature gauge started erratically bouncing around. It would be normal, then bottom out, and then max out momentarily. Multiple "max-outs" would set a code and trigger limp mode because the computer thought it was overheating. It was clearly an electrical issue though because it was bouncing off the extremes.
Anyway, long-story short (and after throwing a lot of parts at it), I de-pinned the signal wire and 5V reference wire for the ECT sensor and created a new set of wiring outside of the main harness that went to the ECT. It completely solved the problem, but it got me wondering what was going on inside the harness that would make it go from 0V to Max Voltage etc.
Wrong kind of signal. What your temperature sender uses is a voltage reading, the signal wiring I was talking about is for digital transmission.
For future posterity you did the correct repair (this is called an overlay). I don't know if the sensor was 2 wire or 3 wire, so I will explain both.
For a 2 wire system the control module sends a calibrated voltage (in your case 5V) down a wire and into a temperature sensitive resistor. Based on the heat this sensor is submerged in the internal Ohms will consume a known amount of the voltage, and the control module will read the voltage coming back (or in some instanced the amps needed to maintain the set voltage) and calculate the temperature. This is a bit simplified, but you get the point.
For a 3 wire system you have what is known as a voltage divider. Wire A will have the 5V from the control module. Between wire A and wire B there will be a variable resistor. Wire B will be the signal. Between wire B and wire C there will be either a fixed resistor, another variable resistor that is inverted to the A-B resistor. Wire C is the signal return (this is functionally a ground), and the value of wire B is used to calculate the value the sensor is reading.
Based on your symptoms either the 2 wire ground, or the 3 wire C was open, this means that either the module saw an out of range reading, or a maximum value reading.
Thanks so much for taking the time to explain it so clearly.
Good to know I did the correct repair. The vehicle's wiring is in such a delicate state (2009 rust belt vehicle that was neglected) that I didn't want to open up the loom for fear of creating even more issues. It has the 2 wire system.
I'm also a caveman when it comes to understanding electrical issues so I avoided dealing with the wiring for fear of destroying the ECU connector, pins etc. After trying a new ECT sensor, an ECU and various other parts I just bit the bullet in the end and did my best attempt at re-wiring from the ECU (in hindsight I didn't need to de-pin it - I cut the existing wiring too close to the pins and had to remove them and make new connectors from scratch).
Part of growing up is finding a collection of guys. You need an electrical guy, a plumbing guy, a welding guy, eventually you need a tax guy or a design and drafting guy, and sometimes a "shows up at 3 AM without a lot of questions" guy.
When people I know answer with "I know a guy" it's usually me.
LOL, when I bought my GTO nothing electrical worked correctly except engine starting and taillights. When I was pulling the engine I was like "wait a second, where is the ground strap?". Turns out the battery connected to the engine as it should and then the rest of the car got ground from osmosis or high hopes! Most likely the transmission cooler lines maybe gave an intermittent contact as they were the only metal I could think of from motor to body. Fixed the grounds and other wire butchery and surprise, surprise. Everything works now!
You don't really get any significant amount of induction through concentric twisting. You'll often find canbus wires in the center of these bundles and all sorts of signal wires. It's a different story when you've got a lot of current flow or high voltage though.
I wouldn't be too concerned, it's a very common practice in Motorsport.
Checkout the Motorsport Wiring Alliance group on Facebook to learn more!
That's the one thing I said "nah" and paid to avoid the tedium/mess of having to do on a cross-platform swap. Sent it to an online car buddy who had some spare time that I didn't (and he could use some extra cash at the time).
Did a 4AGE 20v swap into an old Celica for an ex, honestly the splicing/re-wrapping wouldn't really have been that bad in that build but I still wasn't interested.
(SICK car BTW. An old Z-car is on my short list of cars I'd instantly grab for a swap project if I ever have the extra space. So cool.)
I’m about to jump into rewiring my 68 valiant this summer with a painless kit and auto meter gauges. How screwed am I? Invested in a hakko soldering station and label maker already.
Dude, one of my first cars was a 71 Valiant 4 door. I didn't really appreciate the car back then, but I love them now! I bought it off an old guy for like $125. He'd come and check on it every now and then while I slowly drove that thing right into the ground. Poor guy.
You'll do awesome! Make sure to make your initial runs with rope. Run it to your furthest tail light for example, and then branch from the main rope to each of your components like marker lights, license plate light, etc. Then you take the rope out and run all of your wires along that rope. I used those black office binder clips to hold the wires together while I ran all the wires. It is so much easier than running each wire in the car.
I had a 71 Camaro that was "my first try." Everywhere that car went, my (Bad) reputation followed. It was awful! This is me trying to atone for my past sins, lol
Every time I look at a rats nest of car wiring I think how much better it would be to just have three wires, pos, neg, data going to microcontrollers at each device. But then you need software and some communication protocol. Then I realize that I’m just reinventing the clusterfuck of modern cars. I prefer the clusterfuck of old car wiring where you can debug anything with just a multimeter.
I'm not done, obviously, but all entry and exit points will have rubber/nylon gromets or something similar to protect the wire against contact with metal. Also I don't like the mesh loom, but I'm going to run with it for a bit to work out any details. And then I'll use heat shrink over everything. If I could do it over, I'd crimp my splices instead of solder.
I highly advise against it, but if you are going to solder like you did here, run all of the wires in the same direction. The way you have it places strain on the solder joint. Run your single wire down the bundle, and loop it back up. You can then heat shrink the loop and it will put any strain on the loop instead of directly on the solder joint.
100% need grommets as you mentioned. You did a great job of looming the harness, but pic 3 for example I will guarantee will wear straight through the convoluted loom and start cutting wires.
The point and single greatest benefit of concentrically twisting the harness is for flexibility. When you heat shrink a harness with something like DR25 it acts like a clamp holding the wires tight together. If the wires are run in a straight line they need to slide independently of each other to bend which is extremely difficult when they're clamped by the heat shrink. When using loom like you are, the wiring can slide next to each other without issue and will be plenty flexible without concentric twisting. It already sounds like you know it's not necessary, but that is the reason you'll see it often in 'mil-spec' harnesses
I do have all the wires run and splice in the same direction, unlike the red and yellow wires in the photo. But it is good to reinforce the importance of that practice.
I don't think I quite understand what you're saying running a single wire down the bundle, and loop it back, but I'd be interested for some clarification. The way I have the splices now, they are about an inch from where the splice exits, so that if something is pulled, the solder joint is set back a bit so that it doesn't experience as much of the pulling force, if that makes sense.
Sounds like you may have already done what I was trying to explain, so kudos again! Sorry I'm terrible at trying to explain over messages. Excuse the shitty diagram here, but this is what I was talking about:
When you have 1 wire splitting into multiple, run them all in the same direction for the splice ("with the bundle"), then take your single wire and loop it back the direction you want it to go. In the top example like your comment image I responded to, the solder joint is under tension and will be fatigued with any movement or vibration. In the bottom example all of the wires are spliced in the same direction (single wire "with the bundle"), then the single wire is looped back the opposite direction that you want to go. Now you are placing the wire itself under tension and the solder joint is fully supported. This does make the splice slightly larger and less pretty, but is necessary for longevity. Note this can also be done with crimped splices. Not shown in the picture, but I typically use an adhesive lined heat shrink over the entire loop itself after I insulate the splice. This is not required, but I like the extra safety and it holds everything in place and helps make sure the minimum bend radius of the wire isn't violated if the harness is put under strain.
Hopefully the image helps all this make a little more sense and doesn't add to the confusion.
I found Nichifu P-series crimps that are a good quarter of the price of the Molex series and work excellently for splices. I've been upgrading my race car's wiring with them as I repair the loom, it's been foolproof and it's so nice to not have to mess with solder while contorting myself inside of a roll cage.
beautiful. i was just about to say the only thing missing is some grommets lol
i personally like to use both crimps and solder in different places, if i had the luxury i would only crimp at multiple wire junctions like this one you have pictured, the crimps do a really great job for that situation its just a little finicky to get them all to line up at the same time.
sourcing connectors and pins for different manufacturers is definitely a huge pain in the ass but having a harness with nice clean terminations and all oem connectors is so satisfying lol
i found some AWESOME fiberglass braided loom on ebay a while back that was super cheap and is legitimately fire proof lol it looks pretty good too but if you cut it the shit turns to dust, probably has asbestos in it but it did great for my loom, just throwing that out there.
I don't actually have any aspirations of making this a top level, best of the best project. My welding/mechanical/body work skills are just nowhere near good enough for that. But I had so much fun with the wiring it motivated me to just keep doing a little more. I disassembled and rebuilt all the switches and replaced every single old wire. All the connectors will be Deutsch Connectors, and I have 3d modeled and am just starting to 3d print the fuse/relay box.
This was a test print so I didn't bother to print all the holes.
My plan is to do things in phases - where I get it running, and drive it for a bit to work out any bugs, and try to verify that my work is adequate, before trying to enclose, or perfect or finish anything. in theory, I want to drive it for a couple of months through the summer, and then bring it back in and improve/iterate as needed. Since this is new to me, I'm not always 100% sure that what I'm doing will give me the results that I want. Plus, it give me a chance to enjoy driving the car between periods of disassembly and work.
I realize the irony of this statement since I've just made a wiring harness that will be very difficult to iterate/modify. But it was fun, and I wanted to try it, so yeah :D
You have much higher attention to organization of your wires than I do. I just make sure it all works and that's good enough. I also thought you were wiring an old Z when going through the pics and then it was confirmed by the last one. I have a 75' 280Z I also wired from scratch.
This is just temporary until I'm satisfied with its function and I know I don't need to change anything. My plan is to drive it for a year, and then fully enclose it in a more robust covering.
Yeah it's nice if you plan to order a new harness for every season, but I would never put something like this in my personal car even if it isn't for road use
LS3. This is my first engine swap, restoration project, so everything is a learning experience, I decided to take the path most travel, so I could get lots of help along the way.
If you need parts let me know! I know a ton of places to get z parts and also where to get things for the LS3. You going to keep it the samenorg8nal color?
Oh cool. Wife has a fancy Sony touchscreen deck and wants the backup camera on it. Im also cleaning up the extra cords and ripping out a dumb intierior light feature that was installed by previous owner. (remember sex lights? -LOL)
Soldering is fine if you can do it in right environment.
You did nice job, looks really good, however.. Do I really see nearly one piece if harness without points where you can disconnect them to smaller pieces?
Not totally sure what you're asking, but I have everything going straight to the fuse/rely box under the hood (all fuses/relays are located in 1 place). They are roughly separated into three sections: Under hood/front lights(minus engine management/coil/ecm wiring), Under Dash, and Body/rear lights. they are not connected to the fuse/relay box with connectors. Not sure if that is the right or wrong way to do it...
I would put the fuse box and ECU in the cabin if possible so that you don't have to be as paranoid about water getting trapped if you clean the engine. Customarily there would be a bulkhead connector at the firewall and another to separate the engine and/or transmission from the body harness. I would highly suggest using an Anderson SB connector on the battery.
Looks good, wiring is one of my favorite things to mess with, I have made several harnesses from motorcycles to drag cars and it’s always fun to do IMO. I wouldn’t run shrink tubing to cover everything because it will cause heat to build up if you’ve got any resistance issues ever and not to mention it would be a pain to remove a single wire if ever a fault.
Honestly, while the "concentric wiring" style of wiring is compact, and functional in many ways, it doesn't lend itself well to modification. It is not easy to add a wire, or follow a trail. For a guy that has never done this before, and more than likely has forgotten something, it may prove to be a mistake over just running the wire straight through. I think this style of wiring is much better for highly refined and fully thought out projects. I have added like 3-4 extra wires in several of the runs to hopefully futureproof the wiring a little.
When me and my buddy first started doing wiring on my project car, I was thinking “God this is gonna suck so bad” but it’s not nearly as difficult as I first expected.
The hardest part is finding wire diagrams and figuring out which cut wire I need to wire back up to get something working. Now my problem is when something’s not working, is it the part itself that went bad, the part controlling it, or the wires running to either or between them?
The first thing I did was drew up a diagram for every single circuit. I'm modernizing the wiring, so I have a lot of it going through relays. The lights, and power windows, for example. I love the original column switches, but they're 50 years old, so I don't want to run full current through them anymore, even if it is LED now. Might be overkill, but whatever. Anyway, so I drew up all of the circuits, and then just used those diagrams to run each wire. Every wire also has a heat shrink label on both ends of the wire that tell what they're for.
It does take a lot of work. I have enjoyed it though! Learning a lot. I've never done any of this before. I've dabbled for years working on different cars. Tedious is definitely a good word for many parts of it.
Competitive-Dig-3411@reddit
I had a 1971 240Z that I brought back from California to Michigan. It lasted 1 year. Loved that car.
Competitive-Dig-3411@reddit
280Z ?
ironman454@reddit (OP)
260
Takesit88@reddit
Nice use of snakeskin. I'd recommend a grommet on the pass-throughs that don't have the radiused edges. Even with the chafe wrap, they will wear in with time. Would be a good time to run any audio or data wires in a shielded parallel chase.
Transmechanic420@reddit
This looks more tight then some of the Toyota's come delivered from factory, nice job man! One more tip but maybe you already had this idea. Where the cable bundle comes through metal holes, especially the one cut out in the second pic. Put some extra rubber around the cable there or rtv, or else the metal will eat through the cables.
Thommyknocker@reddit
Holy crap! Only thing I see is you may want to shove a rubber grommet on the hole in picture 2. It's surprising how fast those edges can eat though looms.
I really wish I could fixate on a project like this. The best I can do is get everything in loom not wrapped up like this.
ScottyArrgh@reddit
Just out of curiosity, why wrap/twist the wire like that? Doesn’t that mean you have to run a lot more wire since some of the length is used up in twists? Also tracing/repairing would be a nightmare I would think.
Why not run the strands together and use a sheath to add strength and protection?
ironman454@reddit (OP)
My brother and I have enjoyed content from a company called HP Academy that have courses on different aspects of motorsports, typically racing focused. They go into the wiring techniques that they use, and I've followed along. It does make adding wiring more difficult. But I have not shown that each wire will have a heat shrink label on it that indicates it's use. So instead of wondering what the white wire with red stripe does, it will just have a label on it that says what it does, and a matching label on the other end of the same wire.
SightUnseen1337@reddit
We don't do it this way in aerospace. Pretty much everything is twisted pair and straight bundled on a jig board so that the completed harness has "memory" of the shape and drops in place easily. Individual wire labels and colors just make assembling the harness more tedious, stocking parts more difficult, and inspection impossible. Connectors are labeled on both sides with the name of the assembly, the specific connector of the assembly, and the signal name. We use white for everything because it's easy to tell when its been charred.
If there's a problem with the harness you'll have to hack into it to fix it anyway so you can just use a multimeter to find where the broken wire goes.
linkwolf98@reddit
No we don’t, in aerospace we twist and braid most of our harnesses. I worked on F15, F18, V22, CH47, AH6, AH64, 737, 747 and a handful of other commercial and defense aircraft. I’d say at least 90% of our harnesses were twisted for flexibility and also gave rigidity to branches and locations whether using tape and braid or string ties.
SightUnseen1337@reddit
My experience is with the space part. There's a lot of stuff I made in that rats nest of wire they call a space station lol
mCProgram@reddit
Only canbus needs to be twisted pair on automotive so it tends to be moot to do that for the entire harness. They are an absolute bitch to splice into this way and keep looking nice though.
SightUnseen1337@reddit
Twisted pair is great for just about anything. Having an insensitive aggressor signal like a solenoid or motor on twisted pair decreases the size of its magnetic field further shielding data lines in the same bundle. It also lets you bus your grounds to a single junction instead of having to diagnose bad chassis grounds.
ironman454@reddit (OP)
Very interesting.
linkwolf98@reddit
As a person who has made professional wiring harnesses for aircraft, the reason we twisted and made different types of braids etc, was for rigidity in certain areas and flexibility in others.
ScottyArrgh@reddit
I love HP Academy, and I have several of their books. I will have to look up the wiring that this is centered around.
My concern for you is that this is a personal project car and that serviceability and simplicity would go a long way — you aren’t a Motorsport team with deep pockets that can just replace things wholesale if they go bad (are you?).
Based on my own personal experiences with project cars, simplicity certainly has its place. But maybe that’s just my anxiety talking and there’s nothing to worry about.
I do say, it certainly looks really nice :)
AwwFuckThis@reddit
I love HP Academy.
mr_j_12@reddit
Hp academy is amazing. I'd invest in the wiring course but i have an auto elec mate if i need for those sorta jobs.
Lookwhoiswinning@reddit
The benefits to true concentric twist wiring are that it’s sealed end-to-end and that the twist allows inherent strain relief along the whole run. You are correct about the weight and lack of serviceability, but typically this style of harness is made with aerospace connectors, tefzel (MIL-22759) wire, are sheathed in RayChem DR-25, and have epoxy in every breakout. They are not made to be serviced, instead just completely replaced from bulkhead to bulkhead.
ScottyArrgh@reddit
Ah okay. And I get the benefits of all the things you just said.
Having said that, this is going in a project car where I would think serviceability rather than wholesale replacement would be beneficial.
If it were going into a jet or a space shuttle, then all things you said make more sense to me.
ATILLA_TURK@reddit
Agree may have advantages is some advanced applications but no that I can think of in a car. I have made a few wiring harnesses and would not suggest this
NaniwasWarship@reddit
Very clean!!! Looks good!!
oli55256@reddit
Very very clean i like it alot, my only gripe would be if one of those inner looped wires ever needs replaced its gonna be bitch, unless I'm overlooking something that it wouldn't be?
ironman454@reddit (OP)
You are absolutely right. By the time I'm done with this project I'll have a beautiful concentric wiring harness, with a rats nest of addons bundled with it! :D
oli55256@reddit
If a wire ever goes bad, don't remove it just add another wire to the outer loop lol
ironman454@reddit (OP)
Exactly. I'm going to update in a few years, and ya'll are going to be really disappointed in me.
omegaproject01@reddit
Doesn’t that just add more wire making it more expensive and heavy?
Material-Job-1928@reddit
That looks clean as hell, I hope nothing in that bundle is a signal wire (induction)
ironman454@reddit (OP)
No, this is all just the body wiring. Does the tach signal count? That would be the only one. I bought a harness for the engine management/ecm.
Material-Job-1928@reddit
Tach and speedometer signals should be fine, those are just a pulse. High speed data, and audio signals can develop noise, and cause weird issues.
Also, and I cannot stress this enough, grounds are the most important part of a good harness. Outside of that looks like you are doing a fantastic job.
Any_Championship_674@reddit
Man have I learned that ground lesson a couple of times 🤣
tawmrawff@reddit
I am installing a fitech fuel injection system onto a jeep YJ. they stress that the tach wire should not be next to any other “frequency” wire, like a motor. The induction created by winding the wires is a real possibility apparently. Other than that, it looks great!
whyunowork1@reddit
Yeah........
Those are typically the worst about having noise and being susceptible to bleeding it into the surrounding wire.
Mostly because the pulsed voltage used in most analog tachs and speedos creates an ac charge.
Material-Job-1928@reddit
Really? Well, today I learned. I have always seen that the data wires are affected by induction the worst, and that's why they are a twisted pair in the harness. Doesn't help that most of my formal training was long after speedometer and tach went to data stream instead of pulse drive. I suppose it makes a difference on the pulse drivers if they are pull high, or pull low as to how they respond to unwanted AC current.
whyunowork1@reddit
You misunderstand.
The tach and speedo are the ones creating the noise.
Mainly because they use a magnetically induced charge(this creates the ac current that then bleeds into every other circuit in the harness. 5v sig is the worst effected by it.)
Material-Job-1928@reddit
Thanks for the clarification. I mostly skipped over these problems in my build, The audio sub-harness is actually isolated (by the width of the cabin) from the main harness, and my '86 resto-mod does not have any data wires.
Still, good info if I ever get my next project off the ground, it'll be new enough for data integrity to be a concern.
ironman454@reddit (OP)
Thank you! I never knew until my recent dive into wiring how important grounds are. I don't have those completely clear in my head, so hoping to get some feedback on how and where to put those in.
Material-Job-1928@reddit
Clean, threaded metal, star washers, and covered in dielectric grease. Try to avoid self tapping onto sheet metal wherever practical, and ground all major assembles. Run a ground strap from engine to chassis, and from chassis to body (if applicable). Also, run a dedicated ground from the dash frame to the body panels. When using threaded holes clean them with a thread chaser, and use a new bolt.
Also, there is no such thing a too big a ground. I only used 3 wire sized in my build, 16, 10, and 2. I have a 2 gauge wire fender to block on both sides of the engine bay, and a braided ground from the firewall at the wiper motor to the block. My winch ground shares a stud with the passengers side fender ground stud, and is connected to the primary battery. My amps and inverter are grounded to the rear seat belt capture nuts (did a rear seat delete), and the dash and engine harnesses have a 10 gauge wire running side to side, grounded on both ends, with several junctions in between where the assorted 16 gauge grounds combine to the main ground path.
Yes, I over-did this a little.
SunsetWineParty@reddit
Hey u/Material-Job-1928 would you mind explaining the comment on signal wiring more?
The reason I ask is because I recently had a four-month long problem with my engine coolant sensor. One day my temperature gauge started erratically bouncing around. It would be normal, then bottom out, and then max out momentarily. Multiple "max-outs" would set a code and trigger limp mode because the computer thought it was overheating. It was clearly an electrical issue though because it was bouncing off the extremes.
Anyway, long-story short (and after throwing a lot of parts at it), I de-pinned the signal wire and 5V reference wire for the ECT sensor and created a new set of wiring outside of the main harness that went to the ECT. It completely solved the problem, but it got me wondering what was going on inside the harness that would make it go from 0V to Max Voltage etc.
Material-Job-1928@reddit
Wrong kind of signal. What your temperature sender uses is a voltage reading, the signal wiring I was talking about is for digital transmission.
For future posterity you did the correct repair (this is called an overlay). I don't know if the sensor was 2 wire or 3 wire, so I will explain both.
For a 2 wire system the control module sends a calibrated voltage (in your case 5V) down a wire and into a temperature sensitive resistor. Based on the heat this sensor is submerged in the internal Ohms will consume a known amount of the voltage, and the control module will read the voltage coming back (or in some instanced the amps needed to maintain the set voltage) and calculate the temperature. This is a bit simplified, but you get the point.
For a 3 wire system you have what is known as a voltage divider. Wire A will have the 5V from the control module. Between wire A and wire B there will be a variable resistor. Wire B will be the signal. Between wire B and wire C there will be either a fixed resistor, another variable resistor that is inverted to the A-B resistor. Wire C is the signal return (this is functionally a ground), and the value of wire B is used to calculate the value the sensor is reading.
Based on your symptoms either the 2 wire ground, or the 3 wire C was open, this means that either the module saw an out of range reading, or a maximum value reading.
SunsetWineParty@reddit
Thanks so much for taking the time to explain it so clearly.
Good to know I did the correct repair. The vehicle's wiring is in such a delicate state (2009 rust belt vehicle that was neglected) that I didn't want to open up the loom for fear of creating even more issues. It has the 2 wire system.
I'm also a caveman when it comes to understanding electrical issues so I avoided dealing with the wiring for fear of destroying the ECU connector, pins etc. After trying a new ECT sensor, an ECU and various other parts I just bit the bullet in the end and did my best attempt at re-wiring from the ECU (in hindsight I didn't need to de-pin it - I cut the existing wiring too close to the pins and had to remove them and make new connectors from scratch).
SunsetWineParty@reddit
u/Material-Job-1928 meant to ask, are you a technician by trade? Impressive responses all round!
Material-Job-1928@reddit
Part of growing up is finding a collection of guys. You need an electrical guy, a plumbing guy, a welding guy, eventually you need a tax guy or a design and drafting guy, and sometimes a "shows up at 3 AM without a lot of questions" guy.
When people I know answer with "I know a guy" it's usually me.
ironman454@reddit (OP)
Thank you! It's great to have an example like this to learn from.
Squidking1000@reddit
LOL, when I bought my GTO nothing electrical worked correctly except engine starting and taillights. When I was pulling the engine I was like "wait a second, where is the ground strap?". Turns out the battery connected to the engine as it should and then the rest of the car got ground from osmosis or high hopes! Most likely the transmission cooler lines maybe gave an intermittent contact as they were the only metal I could think of from motor to body. Fixed the grounds and other wire butchery and surprise, surprise. Everything works now!
ASDTuning@reddit
You don't really get any significant amount of induction through concentric twisting. You'll often find canbus wires in the center of these bundles and all sorts of signal wires. It's a different story when you've got a lot of current flow or high voltage though.
I wouldn't be too concerned, it's a very common practice in Motorsport.
Checkout the Motorsport Wiring Alliance group on Facebook to learn more!
elcipse007@reddit
This a great work Keep it up
ecurb599@reddit
Holy shit nice job you absolute fucking psychopath!
crystalgrey@reddit
Great job. Where did you source your wire?
ironman454@reddit (OP)
Its GXL wire from Wirebarn. I also took insight from Superfast Matt. He's got an episode on rewiring your car that gives the basics.
Jean_le_Jedi_Gris@reddit
"attempt" ??
Coffinspired@reddit
Looks great!
That's the one thing I said "nah" and paid to avoid the tedium/mess of having to do on a cross-platform swap. Sent it to an online car buddy who had some spare time that I didn't (and he could use some extra cash at the time).
Did a 4AGE 20v swap into an old Celica for an ex, honestly the splicing/re-wrapping wouldn't really have been that bad in that build but I still wasn't interested.
(SICK car BTW. An old Z-car is on my short list of cars I'd instantly grab for a swap project if I ever have the extra space. So cool.)
mattng99@reddit
I’m about to jump into rewiring my 68 valiant this summer with a painless kit and auto meter gauges. How screwed am I? Invested in a hakko soldering station and label maker already.
ironman454@reddit (OP)
Dude, one of my first cars was a 71 Valiant 4 door. I didn't really appreciate the car back then, but I love them now! I bought it off an old guy for like $125. He'd come and check on it every now and then while I slowly drove that thing right into the ground. Poor guy.
You'll do awesome! Make sure to make your initial runs with rope. Run it to your furthest tail light for example, and then branch from the main rope to each of your components like marker lights, license plate light, etc. Then you take the rope out and run all of your wires along that rope. I used those black office binder clips to hold the wires together while I ran all the wires. It is so much easier than running each wire in the car.
mattng99@reddit
They’re sweet rides and still relatively cheap. Thanks for the advice man! I’ll be sure to do that
MrManSir1974@reddit
Attempt? That looks fan fucking tastic
IntrstlarOvrdrve@reddit
Way better than my first try!
ironman454@reddit (OP)
I had a 71 Camaro that was "my first try." Everywhere that car went, my (Bad) reputation followed. It was awful! This is me trying to atone for my past sins, lol
wanzeo@reddit
Every time I look at a rats nest of car wiring I think how much better it would be to just have three wires, pos, neg, data going to microcontrollers at each device. But then you need software and some communication protocol. Then I realize that I’m just reinventing the clusterfuck of modern cars. I prefer the clusterfuck of old car wiring where you can debug anything with just a multimeter.
ironman454@reddit (OP)
Lots of people are hard at work inventing the future. I enjoy reinventing the past.
Jay-Moah@reddit
Looks really good!
Only thing is I hope you got some grommets. Those bare metal holes will east right through your loom
ironman454@reddit (OP)
Yep. I've got plans for that.
Travisimus@reddit
Cannot get over how picture 8 looks like a hungry hungry hippo having a snack
ironman454@reddit (OP)
Haha, love it.
Paper-street-garage@reddit
Looks good just don’t forget some rubber grommets where they pass through the metal body or some kind of protection.
ironman454@reddit (OP)
For sure. I'm actually 3d printing some nylon sleeves that will protect the wire at those points. They're about 4mm thick
grease_monkey@reddit
You're miles ahead of every other "project" that rolls through my doors. Good work.
underwaterstang@reddit
Thought I was on the FiberOptics sub and I was like what the hell is this
haikusbot@reddit
Thought I was on the
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ironman454@reddit (OP)
I'm not done, obviously, but all entry and exit points will have rubber/nylon gromets or something similar to protect the wire against contact with metal. Also I don't like the mesh loom, but I'm going to run with it for a bit to work out any details. And then I'll use heat shrink over everything. If I could do it over, I'd crimp my splices instead of solder.
ShadeThief@reddit
I highly advise against it, but if you are going to solder like you did here, run all of the wires in the same direction. The way you have it places strain on the solder joint. Run your single wire down the bundle, and loop it back up. You can then heat shrink the loop and it will put any strain on the loop instead of directly on the solder joint.
100% need grommets as you mentioned. You did a great job of looming the harness, but pic 3 for example I will guarantee will wear straight through the convoluted loom and start cutting wires.
The point and single greatest benefit of concentrically twisting the harness is for flexibility. When you heat shrink a harness with something like DR25 it acts like a clamp holding the wires tight together. If the wires are run in a straight line they need to slide independently of each other to bend which is extremely difficult when they're clamped by the heat shrink. When using loom like you are, the wiring can slide next to each other without issue and will be plenty flexible without concentric twisting. It already sounds like you know it's not necessary, but that is the reason you'll see it often in 'mil-spec' harnesses
ironman454@reddit (OP)
I do have all the wires run and splice in the same direction, unlike the red and yellow wires in the photo. But it is good to reinforce the importance of that practice.
I don't think I quite understand what you're saying running a single wire down the bundle, and loop it back, but I'd be interested for some clarification. The way I have the splices now, they are about an inch from where the splice exits, so that if something is pulled, the solder joint is set back a bit so that it doesn't experience as much of the pulling force, if that makes sense.
ShadeThief@reddit
Sounds like you may have already done what I was trying to explain, so kudos again! Sorry I'm terrible at trying to explain over messages. Excuse the shitty diagram here, but this is what I was talking about:
When you have 1 wire splitting into multiple, run them all in the same direction for the splice ("with the bundle"), then take your single wire and loop it back the direction you want it to go. In the top example like your comment image I responded to, the solder joint is under tension and will be fatigued with any movement or vibration. In the bottom example all of the wires are spliced in the same direction (single wire "with the bundle"), then the single wire is looped back the opposite direction that you want to go. Now you are placing the wire itself under tension and the solder joint is fully supported. This does make the splice slightly larger and less pretty, but is necessary for longevity. Note this can also be done with crimped splices. Not shown in the picture, but I typically use an adhesive lined heat shrink over the entire loop itself after I insulate the splice. This is not required, but I like the extra safety and it holds everything in place and helps make sure the minimum bend radius of the wire isn't violated if the harness is put under strain.
Hopefully the image helps all this make a little more sense and doesn't add to the confusion.
pzduniak@reddit
I found Nichifu P-series crimps that are a good quarter of the price of the Molex series and work excellently for splices. I've been upgrading my race car's wiring with them as I repair the loom, it's been foolproof and it's so nice to not have to mess with solder while contorting myself inside of a roll cage.
Pistonenvy2@reddit
beautiful. i was just about to say the only thing missing is some grommets lol
i personally like to use both crimps and solder in different places, if i had the luxury i would only crimp at multiple wire junctions like this one you have pictured, the crimps do a really great job for that situation its just a little finicky to get them all to line up at the same time.
sourcing connectors and pins for different manufacturers is definitely a huge pain in the ass but having a harness with nice clean terminations and all oem connectors is so satisfying lol
i found some AWESOME fiberglass braided loom on ebay a while back that was super cheap and is legitimately fire proof lol it looks pretty good too but if you cut it the shit turns to dust, probably has asbestos in it but it did great for my loom, just throwing that out there.
ironman454@reddit (OP)
I don't actually have any aspirations of making this a top level, best of the best project. My welding/mechanical/body work skills are just nowhere near good enough for that. But I had so much fun with the wiring it motivated me to just keep doing a little more. I disassembled and rebuilt all the switches and replaced every single old wire. All the connectors will be Deutsch Connectors, and I have 3d modeled and am just starting to 3d print the fuse/relay box.
This was a test print so I didn't bother to print all the holes.
Pistonenvy2@reddit
nah man youre doing great work, i love to see this kind of stuff. you should be very proud.
Grouchy_Explorer_243@reddit
doing the wiring and getting the car to run before welding and painting is a gamechanger
ironman454@reddit (OP)
My plan is to do things in phases - where I get it running, and drive it for a bit to work out any bugs, and try to verify that my work is adequate, before trying to enclose, or perfect or finish anything. in theory, I want to drive it for a couple of months through the summer, and then bring it back in and improve/iterate as needed. Since this is new to me, I'm not always 100% sure that what I'm doing will give me the results that I want. Plus, it give me a chance to enjoy driving the car between periods of disassembly and work.
I realize the irony of this statement since I've just made a wiring harness that will be very difficult to iterate/modify. But it was fun, and I wanted to try it, so yeah :D
motohavoc@reddit
You have much higher attention to organization of your wires than I do. I just make sure it all works and that's good enough. I also thought you were wiring an old Z when going through the pics and then it was confirmed by the last one. I have a 75' 280Z I also wired from scratch.
ironman454@reddit (OP)
Awesome! I'm hoping to have it driving by the end of the summer, then back in the garage for more work through the winter.
RelevantlyCasual@reddit
Who did you purchase the braided wire loom from would you use it again?
ironman454@reddit (OP)
I made it myself using this as a guide: https://www.youtube.com/watch?v=dsgUhNH7F7k
RelevantlyCasual@reddit
They are fantastic!
I however asked my question poorly, I meant the protective mesh sleeve. The one I used last for a AV project has held up terribly.
ironman454@reddit (OP)
This is just temporary until I'm satisfied with its function and I know I don't need to change anything. My plan is to drive it for a year, and then fully enclose it in a more robust covering.
RelevantlyCasual@reddit
My temporary becomes long term too often. Hope it works out well for you!
ironman454@reddit (OP)
Well that shitty mesh sleeve will hopefully motivate me. One way or another it probably will.
FalseRelease4@reddit
Why is it wound up like that? Sounds terrible for future repairs or diagnostics
ironman454@reddit (OP)
But it looks so pretty
FalseRelease4@reddit
Yeah it's nice if you plan to order a new harness for every season, but I would never put something like this in my personal car even if it isn't for road use
ironman454@reddit (OP)
Smart.
turboftw@reddit
Looks good!
shrekerecker97@reddit
I actually install wiring cabling for a living, and I'll tell you that looks great!
ironman454@reddit (OP)
Thank you! It's been a lot of fun.
shrekerecker97@reddit
I am a huge z fanatic. What year is that one?
ironman454@reddit (OP)
shrekerecker97@reddit
Original engine or did you do the Chevy 350 conversion?
ironman454@reddit (OP)
LS3. This is my first engine swap, restoration project, so everything is a learning experience, I decided to take the path most travel, so I could get lots of help along the way.
shrekerecker97@reddit
If you need parts let me know! I know a ton of places to get z parts and also where to get things for the LS3. You going to keep it the samenorg8nal color?
Wesgizmo365@reddit
I do too. Usually I have to go to r/aviationmaintenance to see this kind of goodness but it's nice to see it here.
convecks@reddit
This needs to be marked nsfw.
Wizdad-1000@reddit
Reminded me that I have a neat Sat project waiting for me. 3 camera install. 😀
ironman454@reddit (OP)
Nice! I have a rear view mirror that has integrated cameras: https://www.amazon.com/dp/B0895NMDKT?ref_=ppx_hzsearch_conn_dt_b_fed_asin_title_1
Wizdad-1000@reddit
Oh cool. Wife has a fancy Sony touchscreen deck and wants the backup camera on it. Im also cleaning up the extra cords and ripping out a dumb intierior light feature that was installed by previous owner. (remember sex lights? -LOL)
AudienceOdd4685@reddit
Got a Lil chub looking at this. Nice work!
texan01@reddit
that is a work of art!
however, maintaining it would be a nightmare!
Electrical_Walrus_64@reddit
Looks like more than an attempt!
LGCJairen@reddit
Way nicer than my wrapping shitty junkyard pilfered wire in dollar store electrical tape
YousureWannaknow@reddit
Soldering is fine if you can do it in right environment. You did nice job, looks really good, however.. Do I really see nearly one piece if harness without points where you can disconnect them to smaller pieces?
ironman454@reddit (OP)
Not totally sure what you're asking, but I have everything going straight to the fuse/rely box under the hood (all fuses/relays are located in 1 place). They are roughly separated into three sections: Under hood/front lights(minus engine management/coil/ecm wiring), Under Dash, and Body/rear lights. they are not connected to the fuse/relay box with connectors. Not sure if that is the right or wrong way to do it...
SightUnseen1337@reddit
I would put the fuse box and ECU in the cabin if possible so that you don't have to be as paranoid about water getting trapped if you clean the engine. Customarily there would be a bulkhead connector at the firewall and another to separate the engine and/or transmission from the body harness. I would highly suggest using an Anderson SB connector on the battery.
TheHer0br1n3@reddit
That's cleaner than what manufacturers put into cars 🤤
On a side note, when you or any of the next owners ever need to get to one of those cables, they are gonna swear a lot.
Middle_Teaching_5542@reddit
I’ve seen much worse from much more experience. Well done. Now you just need to draw your schematics
ironman454@reddit (OP)
I did that first.
salokin9@reddit
What year Z is it? Any more detail on the car?
ironman454@reddit (OP)
All you need to know. :D
Far-Wave-821@reddit
Looking good to me!
RedditBeginAgain@reddit
Nice. Can you come redo my cars' factory wiring and make them better?
rotard13brew@reddit
This reeks of excellence. Well done
No-Farm-2376@reddit
Looks good, wiring is one of my favorite things to mess with, I have made several harnesses from motorcycles to drag cars and it’s always fun to do IMO. I wouldn’t run shrink tubing to cover everything because it will cause heat to build up if you’ve got any resistance issues ever and not to mention it would be a pain to remove a single wire if ever a fault.
ironman454@reddit (OP)
Honestly, while the "concentric wiring" style of wiring is compact, and functional in many ways, it doesn't lend itself well to modification. It is not easy to add a wire, or follow a trail. For a guy that has never done this before, and more than likely has forgotten something, it may prove to be a mistake over just running the wire straight through. I think this style of wiring is much better for highly refined and fully thought out projects. I have added like 3-4 extra wires in several of the runs to hopefully futureproof the wiring a little.
Jackthedragonkiller@reddit
Nice!
When me and my buddy first started doing wiring on my project car, I was thinking “God this is gonna suck so bad” but it’s not nearly as difficult as I first expected.
The hardest part is finding wire diagrams and figuring out which cut wire I need to wire back up to get something working. Now my problem is when something’s not working, is it the part itself that went bad, the part controlling it, or the wires running to either or between them?
ironman454@reddit (OP)
The first thing I did was drew up a diagram for every single circuit. I'm modernizing the wiring, so I have a lot of it going through relays. The lights, and power windows, for example. I love the original column switches, but they're 50 years old, so I don't want to run full current through them anymore, even if it is LED now. Might be overkill, but whatever. Anyway, so I drew up all of the circuits, and then just used those diagrams to run each wire. Every wire also has a heat shrink label on both ends of the wire that tell what they're for.
StrangeCitizen@reddit
If this is an attempt, then my wiring is a failure.
ironman454@reddit (OP)
Haha, thank you. I keep thinking I'm going to get it all done and then none of it will work. :P
ridiculusvermiculous@reddit
hell yeah!!
NjGTSilver@reddit
Looks good!
Old-Spend-8218@reddit
Wow nice
JustinTime_vz@reddit
Beautiful work!
ZaMelonZonFire@reddit
Nice work! I suspect projects like this start as overwhelming, become tedious before finally being rather rewarding. Am I correct?
ironman454@reddit (OP)
It does take a lot of work. I have enjoyed it though! Learning a lot. I've never done any of this before. I've dabbled for years working on different cars. Tedious is definitely a good word for many parts of it.