The Tale of Antonia

[seabeelt]

I don't believe there is, you would probably have to have something custom made. Most folks swap rear ends (I.e. get an auto trans rear end) to get more cruise speed, but you lose on the lower gears.
R/

[blurple124]

My apologies, friends, for the delay on posts for this year. I assure you, This summer was a great success with lots of good progress, but it turns out that graduating from engineering school is rather difficult. I should have time to put together some good progress reports near Thanksgiving.

In the mean time, I leave you with a photo from this past weekend, as we put the old girl away for another winter.

[blurple124]

This post is long overdue, I know! Nothing like posting on work that was done 7 months ago. As it happens, graduating from engineering school is harder than everyone makes it seem.

So back to it!

Fiat has earned a bit of a reputation for their wiring over the years, and I’m not convinced it was ever truly deserved. I do believe that the wiring harness, as it came from the factory, was well engineered and worked perfectly fine, with the exception of a few things. Unfortunately, over the course of their existence, these cars have run into electrical problems that have since been mitigated in automotive mass production (thankfully!). Chances are pretty good that a lot of these problems are the result of a poor ground or some very minor fault in an otherwise functioning system. Nevertheless, some rather…um…eccentric repairs have been performed to “mend” the issues in many Fiat Spiders. The fact of the matter is, DC wiring is intimidating and doesn’t get the attention it deserves as a result. This seems to be the real root of most electrical problems in these cars.

My Spider is no exception, of course. I admit that, in my haste, I have even performed some less-than-favorable modifications to the electrical system myself. One example being the splice which re-stored power to the starter motor, relieving me of push-starting the car before each drive. Being fully aware of this and many of the other modifications to the wiring in my car, I was more than anxious to update the system. It took a great deal of restraint not to dive into the project, but I knew that my knowledge of the system was limited and that I had only one chance to do the job right. The more prior planning I did, the better the results would be and most importantly, the safer the system would be.

I began by determining whether replacing the electrical system entirely would be the correct approach. The system did function for most of my needs, after all. My turn signals were intermittent, but worked most of the time, and at least one of my side marker lights worked properly. Who needs hazard signals, anyway? Okay, so it wasn’t perfect, but there were many components working just as intended. I kept hearing the adage, “If it ain’t broke, don’t fix it.” My alternative would be to simply replace what needs replacing and leave everything else in place. At this point, though, aren’t I simply furthering the damage to what remained of the original harness? Is this really doing the job right?
If I was going to re-wire the entire car, I had to lay out my goals for doing so:

• The original harness, at 35 years old, would be updated with fresh wires.
• New wires, with higher performing insulation, would have smaller diameters, reducing clutter.
• The exposed Bosch-style fuses are fragile and more difficult to find than more modern fuses. A new fusebox could be chosen to eliminate this issue.
• A new fusebox would allow for additional circuits, if needed.
• Evidence of an electrical fire in the car indicated that more damage may linger within the system. A new harness would eliminate the risk of this causing further damage.
• Several systems, including some emissions control devices, had been removed from the car. The wires that ran to these systems could be removed, making the engine bay cleaner and safer, overall.
• The modified original harness would be removed and replaced with an intact system.
• A brand new harness could be customized to accommodate changes to electrical components in the car.
• More secure grounds would make the system more reliable
• A system that I have designed and installed would be much easier for me to diagnose than the one that it was replacing

Fire hazards like this were a major motivation for replacing the wiring harness. These wires were what remained of the emissions control devices which were previously removed from the engine bay.



The Bosch-style fuses that came in the car are very fragile, and the conducting element is exposed to the cabin air, including the contacts at either end. Even if the fuses were easy to find, this is less than ideal.



This bundle of wires leading to the relay panel in the car gave me the idea that some bulk could be shed from the harness, considering most of the relays were associated with removed emissions hardware.

This was a great deal of motivation for undertaking the task, so I proceeded to plan the system properly. I filled notebooks with changes that I wanted to make to the system and wiring diagrams that would make them possible. I scoured the web and my own papers for documentation on the original wiring system. I created list-upon-list of the electrical components that were in the car. I gathered as much information as I could in order to get a good idea of what was required to develop a usable system. Eventually, all of this information went into an excel spreadsheet. Call me an engineer, but I love my spreadsheets!

For the sake of readability, I will save the spreadsheets for chapter II of this electrical adventure. This project would ultimately be a large part of the work I complete on the car during the summer of 2013, and while it seemed like slow progress with all of the planning, I knew all along that it was entirely different than the work I did previously. This was slow and tedious, which would pay off in the end. But more on that later! For now, I simply wanted to introduce the project and leave you all with the comfort of knowing that I had not abandoned this project! There is a lot to tell here, and I have been so caught up in the rest of my work that I have simply neglected to maintain these posts. There is more to come, in short time!

[perthling]

Nice to see someone taking a measured approach to this kind of issue - too often we see people dive in, create some additional unanticipated problems, and the whole thing gets beyond them and the car ends up sitting there for evermore.

[deftone]

Nice to see someone taking a measured approach to this kind of issue - too often we see people dive in, create some additional unanticipated problems, and the whole thing gets beyond them and the car ends up sitting there for evermore.

who? Me?

[blurple124]

The next step in my planning process involved a lot of measurement and calculations. My first order of business was to figure out exactly what was in the car originally. Using the electrical section of Fiat’s shop manual, I created a list of every electrical component in the car. From this list, I marked which components I would be retaining, which would be removed, and wrote down any I intended to add.

With a measuring tape, I determined roughly how far each component was from the source of power (i.e. the fuse box). Next, I used a digital multi meter to get an idea of the current draw for each component and double-checked to make sure the voltage was about 12v. This information was included on my list of components, along with which fuse each item was on and which switch, if any, was used to activate that component. Eventually, the list below was developed to show all of this data. This table was formatted to allow sorting and filters within any of the columns, helping me to focus on certain aspects of the system.



Each item is color coded according to the fuse it was ultimately assigned to.


This process was followed by writing a list of logic statements. This was an easier way to figure out which switches were needed for which functions and which items needed to be grouped together. I listed things like “If the key is in the start position, then the starter solenoid will be energized and all circuits that are energized in the run position.” There are a few changes that I decided to make the system, since I was allowed some freedom in my design. Here are some examples:

• The fuse box would be split into two circuits: Those that are energized at all times (such as the clock and ignition switch) and those that are energized only with the key in the run position (I referred to this as the “switched” side).
• Power is run directly from the battery to the starter motor, then from the starter motor to the fuse box, rather than running through switches before fuses.
• Relays would be added for high-current items such as headlights, horns, windshield wipers, and activating the “switched” half of the fuse box.
• Engine bay, trunk, and courtesy lights would all be added and independently switched.
• The radio will have power when the key is in the ignition, even if the switch isn’t in the run position. This acts like an accessory position that is available on modern cars, and took advantage of the key-warning alarm switch.
• All lights will be replaced with LEDs with the exception of the headlights and the battery-charge indicator light (a diode prevents this circuit from functioning properly).
• The windshield wipers would be actuated using a programmable logic controller (in my case an Arduino nano). For those not familiar, Arduino is a great C++ based open-source platform with some handy microcontrollers. I wanted to put one to use!

Laying this all out really helped me wrap my head around the job and figure out how I was going to make everything work. As I mentioned in the last post, I hand-drew many circuit diagrams in my notebooks trying to figure out the best way to lay out each system and reduce cost. To make this easier, I developed a list of diagram codes to denote each switch, relay, component, light, and indicator that would end up on the car. Each of these items had a 2 or 3 letter code associated with it to make the diagrams cleaner. The picture below shows many of the codes I used. I am in the process of creating a digital wiring diagram for my system using this same convention. This will help me to diagnose issues, allow others to create a similar system if they so choose, and help a future owner of my car understand the system, should I ever part with it.



After I had figured out each circuit, I had to figure out how to distribute power efficiently. I knew that if I had too much distance between a fuse and a component, I would need larger gauge wire to keep it safe, and that would cost more money. This would also result in more voltage losses and lead to many of the problems that plague Fiat Spiders today. Short wire runs were a priority for this system, especially on high current components. As a result, I began tabulating the location, current draw, switch, and supply fuse for every component in the system. I created maps of where higher power items are in the car to centralize the location of the fuse box and relay board.

A great deal of deliberation followed, as was often the case throughout this project, but I ultimately decided that a fuse box could be enclosed in the engine bay, protecting it from the elements and I could install fuses in that same box – akin to the fuse/relay boxes found on many modern cars. Using the measurements taken before, I created a variation of the table listing components and their current draw to include their approximate distance from the proposed fuse box location. From this, I used Ohm’s law to tabulate the voltage drop for each component if the circuit were connected using 18 AWG, 16 AWG, 14 AWG, 12 AWG, and 4 AWG. This table is also sortable so that I could identify high power items, long wire lengths, or high voltage drops within the harness.



Using this chart, I was able to select appropriately sized wire and purchase it in bulk. For constant-power components, voltage drop greater than 0.1v was unacceptable. This number was a bit arbitrary, and I really should have determined the insulation capabilities of the wire I was using, and then backed out the power dissipation it could handle and used that number to figure out an acceptable voltage drop, but I felt that my value was conservative enough to avoid any problems. I ended up choosing 16 gauge and 14 gauge for most items, then using 4 AWG to bring power from the starter post (where the battery cable comes in from the rear-mounted battery) to the fuse box.

The last major stage of designing the system was to balance the circuits. I had chosen a marine fuse box made by Blue Sea Systems which had 12 fuses all supplied by a single bus bar and included a grounding post with terminals.



Modifications have been performed to this style of fuse box, splitting it into two bus bars, rather than one. This was my intent and how I planned to achieve a set of “hot” fuses and a set of “switched” fuses. I had to ensure that all electrical components were divided among these 12 fuses in a way that made the following possible:

• Components were on the appropriate bus bar (“hot” or “switched”).
• No single fuse had significantly more current flowing through it than the others.
• Similar components were on a common fuse.
• Loss of a single fuse would not make the car unsafe (all headlights couldn’t simultaneously go out at night, for example).
• High current items and low current items were separated where possible so that fuses would protect low power components (critical with a high number of LEDs in the car).
• Two fuses were spared to allow expansion of the electrical system, should accessories be added in the future.

It was no easy feat balancing all of these needs, but a proper electrical system should have these features, at least. Finally, I decided on a layout that made most of this possible. I did this by assigning fuse numbers to components in my tables and totaling the current draw of components on each fuse. This also helped to determine what size fuse each circuit would need. The system I created is shown below, along with a sample of a more detailed list that I created earlier on.



Each block represents a wire leaving the fuse block, color coded by the wire color that would eventually be used.



The relative load of each fused component was identified by the shade of green for that box.


This wraps up the majority of the design work that I had to do before I could start construction. Forgive me if this sounds a bit like a design report – I have been writing quite a few of those recently and I see it rubbing off in my leisure. I have now introduced my re-wire project and detailed the design of it. Next up is the exciting (and scary) bit: construction and installation. Stay tuned!

[RRoller123]

Holy moly! Now that is dedication! Good work.

[blurple124]

I will offer full disclosure here – the decision to finally implement the plan described in the previous post started out as a decision to remove the transmission and address its issues. My parents were leaving for a vacation while I opted to stay home and work, so I was hesitant to tackle a job like the transmission for fear of being overwhelmed or doing damage. Nevertheless, I thought I could do some prep work, such as removing the center console to access the shift lever and disconnect any plugs. As I dug into the car’s interior, something happened that I didn't imagine would: I became even more scared about the state of the car’s “functional” electrical system.

It had become apparent to me that my car should not be driven much longer without a complete overhaul of the electrical system. To give you some kind of an idea of what I discovered as I removed the existing harness, there was an AC power cord with both leads stripped and wrapped in electrical tape on one end, and on the other attached to a small transformer, which had no other outputs of its own. Perhaps it was this same electrician that completed a circuit by splicing a black 14 AWG wire into two 16 AWG wire, back into a black 16 AWG wire, and finally into two 16 AWG wires which split into their own separate circuits, one of which had an inline fuse in addition to the one in the original fuse box. Beyond this were the burned connectors (like the one responsible for the no-starter problem that I faced when I first purchased the car), a melted wire from an electrical fire, a rat’s nest of wires left in the engine bay after I had removed the emissions equipment from the car, and a half-baked solution to the lack of turn signals. Among the components that didn't work before beginning this project were hazards, reverse lights, courtesy lights, engine bay lights, the trunk light, the handbrake on/low brake fluid warning light, the seat belt warning light, and at times even the turn signals. Needless to say, proper repairs were required. Before long, the car had begun to look like a jungle of very colorful spaghetti.



This is what happens when automotive electricians have too much pasta in their diet.


Before completely removing any wire from the car, I used a label maker I had purchased for this job to label as many of the original wires as I could. My hope is that this will make the harness more useful to someone else who might need it, since a good portion could be salvaged. Once that tedious task was completed, I went about disconnecting everything and, before too long, I had the harness in my hands!


Although it took some time, having the original harness labelled could prove to be convenient if it ever needs to be reused, and it served as a good reference when building the new one.


At this point, I had already purchased many of the materials I would be using. I was attempting to do the best job I could with relatively inexpensive materials, so the wire I used was PVC coated from EBay and not GXL wire like I would have preferred, given enough money to spend on the job. Also from EBay, I had purchased LED replacement bulbs for all of the lights; a roll of flexible LED strip to use as courtesy lights; Bosch-style relays, including two electronic flasher relays for the turn signals and hazards; expandable, braided wire loom; a 4 gauge wire for bringing power to the fuse box; a high-current, solenoid-style relay (typically used as a starter solenoid for lawn tractors) to activate the “switched” section of the fuse box; plenty of heat shrink tubing and a heat gun to apply it. During the project, I also purchased dielectric grease, crimp-style spade terminals, and a set of automotive-style multi-pin connectors. These pin-and-socket style connectors allowed me to create up to 15-wire connections from the harness to the vehicles components so that one could be removed without the other, similar to the way the original harness is. The total cost of the project was less than $200, including the $50 fuse box from blue seas.

At this point, the car was free of 95% of all wires, and it was time to begin the construction process. Before that could happen, however, I needed to determine where the fuse and relay box would be located, and that meant designing it to know that it would fit. I fired up SolidWorks on my school laptop and began working with the sheet metal tool to sketch up some basic designs. The goal here was to shape something that all the electrical components would fit into comfortably and that would fit into the car comfortably, in addition to being simple and easy to manufacture quickly, since I would be asking the engineering model shop at my father’s workplace (and my previous summer employer) to help me build it out of stainless steel. The design I chose was based on locating the box on the left side of the engine bay. This kept it relatively close to many of the high-power electrical components, such as the engine fan, headlights, radio, and horn.


This is a solid model that I created in designing the fuse box and relay containment box.

Building the wiring harness was relatively simple, now that all the planning had been done and I had a clear idea of what I was doing, but it certainly took a long time. Using one of my spreadsheets, I was able to sort the list of components to show all of the wires that departed from a certain location (the steering column, for example) or those that arrived at a certain location. Using these lists, I would run a wire from one its origin to its destination, leave some excess length to ensure that there would be enough, cut it from the spool, label the wire, and add the wire color to the spreadsheet. By doing the job this way, I was always aware of which wires had not been added to the system, and it was easy to determine where I needed to work next. Slowly, but surely, I created my own forest of spaghetti, and soon took to bundling it with cable-ties.


A bundle of newly run wires can be seen exiting the firewall and running down the driver's side of the engine bay to the location of the new fuse/relay box.

When the wires were cut and bundled, I pulled the beginnings of my harness out of the car to begin attaching the multi-pin connectors. All connections on the harness remained female, just as in the original, so the task was methodical and tedious, more than it was challenging. The end of each wire was stripped, crimped into the pin (I had only a needle-nose pliers to crimp this style of pin), soldered for safe measure, and protected with heat shrink tubing. By the time I had finished more than 120 connections on the harness alone, I was quite proficient at this process.


Some completed female pins: crimped, soldered, and heat shrink-wrapped.

Before the pins could be inserted into their connectors, I wrapped the harness in the expandable wire loom that I had purchased, using electrical tape to prevent fraying at any junctions or ends were the loom had been severed. Once the loom was on, I began inserting the pins into their respective connectors. Determining which wires belonged to which connectors was done carefully, as there is a limit to how much current can be run through each size connector. I kept track of which wires were in which position in yet another spreadsheet that I put together. Before I knew it, the wiring harness had been completed! The next challenge was to wire everything that would connect to it.

I decided to make some changes to the switch layout by removing the existing panel in the center of the car’s dashboard and replacing it with a panel that contained switches and indicators which were more useful to me. Five switches were used for lighting (night, parking, and off), courtesy lights, hazards, wiper motor speed, and engine bay lights, while four LED lights indicated turn signals/hazards, and handbrake on/low brake fluid level. While I had to wait some time for the panel itself to be fabricated, I was able to wire all of the toggle switches (toggle switches aren’t legal in production cars anymore, but it is such a classic look that I couldn’t resist!). One-by-one I crimped terminals and ran wires, putting pins on each and plugging them into their connectors. The gauge panel, the control panel, the headlights, the wiper motor; I whittled the list away until I faced the fuse box.


In this photo, two 4-wire connectors can be seen, which allow a secure and protected connection within the circuit; above them, one of the LED strips used to illuminate the engine bay can be seen.

I had to open the fuse box up and literally sever the bus bar that connected the input terminal post to each of the fuse positions. I drilled a hole and inserted a new post, then connected that post to the disconnected section of bus bar. After this came the challenge of putting wires on all of the correct terminals – a task that was, once again, aided by my spreadsheets.


The bus bar inside the fuse box was separated, and this section was connected to a separate terminal post which I installed into the fuse block.


The separated bus bar is shown re-installed in the fuse box. The machine screw acts as a secondary terminal post for the "switched" power input.


The finished product can be seen with two power inputs: the right input is always live, while the left is energized by the ignition switch.

At this point, I had completed wiring the electrical system. I have spared you some of the monotony, describing the construction in mere paragraphs, but in my mind this seems more an epoch than a journal entry. Nevertheless, the most rewarding part is to come, for we have reached the part of the story I have been so anxious to share with all of you – the results. After everything was properly installed and the car’s interior was reassembled, I gathered some pictures to share with everyone.


This is the completed fuse/relay box, in its final resting place.


With the fuse and relay box opened up, fuses are easily accessible, and the relays that lie below are identified using the labels on the box walls.


This is one example of the braided wire loom where the harness branches off in two directions. The loom is secured using electrical tape and reduces clutter, while still allowing airflow to the wires (increasing current carrying capacity slightly). The speaker wire and ground wire have since been secured behind the dash, but this photo was taken before that was done.

My goal was to have the car completed in time for my aunt’s 60th birthday celebration, since my family would be coming from around the country to visit us in Door County. I wanted to show off my baby, and not have her in a tangle of wires in the garage! Mission accomplished. Frankly, I was surprised at how well everything turned out. Admittedly, I ran into a few issues in the first attempt to energize the system. Several fuses blew, indicating that I had shorted out the internals of my fuse box during modifications, but I was able to remove it, open it up, and make adjustments in a matter of a couple hours. I found that I had accidentally mis-matched the high-beam and low-beam leads for the right headlight, which led to some entertaining confusion prior to their being switched appropriately. I have put at least 150 miles on the car since the rebuild and everything is working just as I intended it, which makes me extremely pleased!

Two more sheet metal parts that I had assistance fabricating were the switch panel and the panels for my new speakers. I am not entirely sure if the speakers in the car were installed by FIAT or by a previous owner, but I can only assume the latter. The speaker faces were 6" x 6" squares, protruding from the inner door panel. As a result of this, the window crank would hit the speaker, damaging both components. This seemed like an excellent opportunity to upgrade my audio system! I purchased 3.5" round speakers made by Polk, then designed adapting plates that would cover the original speaker holes and use the same mounting points. Once they were made, I took a wire brush to them to get a nice brushed surface finish.


The speaker panel uses the same mounting holes as the old speakers and covers the old hole, while allowing the window crank to clear. I used a wire brush to give the stainless panels a softer look.

The switch panel is a custom design and actually incorporates the golden ratio several times, for those of you who are aesthetically inclined! The challenge with the panel was fastening it to the dashboard. I had to cut out the metal backing plate that held the original center dash in place so that the switches would fit. I eventually decided that magnetically fastening the panel to the dash would make modification easy and avoid fasteners ruining the look of the dash that I had intended. I bolted four rare-earth magnets in the corners of the mounting location with spacers to offset the panel somewhat (for switch clearance). The panel itself was austenitic stainless, so it was not magnetic. To create a magnetic surface for the magnets to stick to, I grabbed some 1" wide strips of ferritic stainless steel and bonded them using 3M VHB mounting tape (awesome stuff). The panel snaps right into place (the exact position is adjustable) and doesn't move at all during driving or when using the switches.


Four rare-earth magnets hold the switch panel in place. The offset allows the switches and wires to clear the upper heating duct.


This switch panel was laser cut from engine turned stainless steel. The five switches, from left to right, select wiper motor speed (high/low), courtesy lights (on/automatic with open doors), exterior/dash lighting (off/park (dusk)/night (on)), trunk lights (on/off), and hazards (on/off). Below them, the outermost red LEDs blink with the right or left turn signals, respectively, or the hazards, while the inner two indicate low brake fluid or an active handbrake.

There were a couple of things that I did not get a chance to wrap up before leaving for school, but it is something I look forward to finishing in the future. My wiper motor controller was malfunctioning in some situations (likely due to a subtle error I made in my coding that I was not aware of), so I temporarily programmed the Arduino controller to turn the wipers on or off, rather than accommodate the delay function that I had hoped to include. The existing switch on the clutch pedal is a normally open switch used for the emissions system, but I hope to replace it with a normally closed switch so that I can use it as a “safety switch” that prevents the car from being started without the clutch pedal depressed.


This circuit switches the relay in the fuse box that brings power to the wiper motor. The black microchip is a programmable micro controller designed to operate using open-source Arduino software.

Other than that, I simply have to wire and mount a snap-action switch that activates the trunk light as the trunk-lid is opened. I look forward to completing this, after seeing the results of my other courtesy lighting. I have three courtesy lights in the cabin which can be turned on manually or are activated when either door is opened. One light is in each foot well, while the third hides behind the mesh panel below the stereo and is completely invisible until it is turned on! The engine bay lights have already come in handy for a fuse change that I had to do at night during the first headlight testing. They illuminate all of the areas of the engine bay that might need attention: carburetor, dipstick, fuse box, etc. Very handy!


Three LED strips illuminate the foot wells and the center console (where keys might be sitting in the dark). *I apologize that there isn't a better photo, perhaps in the future I will change that!


A teaser shot of how well the engine bay lights illuminate the under-hood area.

[Exit98]

Charlie,

I'm speechless.

Amazing.

How much to do mine?

[RRoller123]

ABSOLUTELY FANTASTIC!

[blurple124]

Thanks, guys!
It took some time, but I'm really happy with the results.

I'm sorry the images are wider than the site allows. I tried fixing the issue, but it doesn't seem to have worked. If need be, you can always open each one in a new page.

[georgeramos]

All your work and progress has been inspirational and amazing. The wiring frankly is mind-blowing! Genius.

[Redline]

so the wire I used was PVC coated from EBay and not GXL wire like I would have preferred, given enough money to spend on the job

Do you think this makes much difference under-hood (temperatures)? I'm planning some re-wiring and tidying over next winter and just starting to get my thoughts together.

[ScotcH]

Looks like a great project dude! I've wired race cars in the past, and know it's a tedious job ... but somehow I enjoy it. it's very satifactory to have the wires nicely bundled and routed neatly!

Couple of questions:

1. Don't suppose you'd want to share some of your spreadsheets? I know it's a custom job, but would give me a huge head start for when I tackle mine this winter!

2. 14 and 16 gauge wires seem like overkill. Certainly not an issue to go that big, but typically, the wires I work with a 18 and 16, and many circuit even use 22 (5v sensors, which I know we don't have). Is it just that these old ass components are such power hogs compared to "modern" electronics? I do see that many of the wires in the stock harness are pretty big, but I assumed that is due to the inculation, as they just seem to hang out in the engine bay, without proper routing or wiring channels to protect them.

[blurple124]

Hello everyone!

My regrets on the long hiatus from this forum! I just started work at Tesla a few weeks ago and things have been NUTS. As a result, I've had to move and leave my spider behind (for now!).

In spite of this, BEEK has been a great help in helping me to rebuild the transmission on my car. Installation of that beauty along with a new clutch and a few other improvements will all be complete by the end of this month, before the car goes into winter storage (hopefully the last winter she has to put up with before moving to California!). Once all of that is done, I'll come back with a bigger update.

For now, I wanted to pay some attention to the recent comments.

Redline: The PVC coated wire is rated to a temperature of at least 80 C (176 F). Considering the engine has an operating temperature of 180 F and the wires are in open wire loom at the side of the engine bay, this might be safe. That being said, it is probably the weak link of the entire job. GXL wire is rated to 125 C (257 F), so it would be the much smarter choice for the job. I did my best to avoid heat sources and protect the wires. The insulation on the original harness is probably very similar to the PVC that I used and it held up fairly well over the years. I may have to replace the wires that are run closer to the exhaust or engine, but I will monitor that to see if it is necessary.


ScotcH: I sent you a message, so check that out. As for the wire gauge, I set up my wiring to achieve at most a 1v drop over any given length. The 16 was about right, if not overkill, but the 14 was often pretty conservative. I wanted to avoid the dreaded voltage drop that plagues our cars (that and grounding issues). There are a lot of cases where 18 and 20 gauge wire would have worked, but it was cheaper to buy 16 in bulk and use it everywhere. Keep in mind, modern insulation is thinner than the old stuff, so I wasn't adding too much bulk to the harness by bumping the gauge up, either. And as for the routing you mentioned in the engine bay - I totally agree, that's a big reason I wanted a refresh of the system!


More to come, my friends. As Arnie says - I'll be back.