The Road to Speed Week 2014 Part 3: Gettin’ Wired With Zombie Vampire!
The countdown to Speed Week is well underway, which means that pretty much everything becomes secondary to getting the car put back together. One of the most important additions to Project 240SX LSR this year is the new wire harness, the sole informational network responsible for making sure that the car is able to operate to its full potential, and also do it reliably. As covered in a previous update, the old wire harness which was completed as the car was literally being loaded on the trailer accomplished the goal of getting the car to the salt. However, we knew that it would need to be upgraded in the interest of reliability for future seasons. Well, the future is now, and the new wire harness is built to perform.
Of course, quality materials are only as good as their assembly. With that being said, let’s take a closer look at how the harness for Project 240SX LSR was painstakingly constructed, lead by lead by our resident Zombie Vampire extraordinaire, Nick Hunter, 5523 Motorsports’ Jen-Bot and Zombie buddy Evan Dunham (+ dog Zeus).
The benefits of having a proper motorsports grade wire harness are numerous, from having reliability enhancing, continuous leads from end to end, high levels of durability from the almost-everything-proof Raychem DR25 outer jacketing, lightweight and chemical/abrasion resistant aerospace grade Tefzel wiring, in addition to the use of water/dust/salt resistant circular connectors and Deutsch DTM connectors. The combined benefits of each of these components will no doubt come in handy under the harsh conditions of the Bonneville salt. The harness also looks a heck of a lot nicer than the yards of exposed wiring that used to run throughout the car.
Planning is everything. Here, Nick and Jen-Bot record the functions of each individual wire. These notes will be key in creating wiring schematics for the entire harness later on down the line. Wiring schematics?! I think someone’s race car just leveled up!
At this point, the wire bundles were stripped of the zip ties used in forming the harness, and secured using either spot ties or lacing (spot ties for shorter segments, and lacing for longer portions) for proper anal retentive Zombie Vampire status wire management. For Project 240SX LSR, Nick has taken a page from the NASA specification manual and hand tied hundreds of tiny knots, most likely while fueled by nothing other than grape 5-hour ENERGY chased by Dr. Pepper.
Each leg of the harness is laid out in the car and trimmed to ensure a perfect fit. Every wire, regardless of its location in the car or function, receives the same bulletproof connector treatment. Here we see the Garmin GPS units connected to the harness via a Deutsch DTM connector.
Zombie Vampires love knots. Spot ties are not only used in the wire harness, but also have been applied everywhere throughout the car, from the wires behind the center console, to the coil pack wiring in the engine bay as shown here. Due to his diligence, Nick is well on his way to achieving his goal of using up the entire San Diego area’s supply of waxed spot tying thread.
Gold plated pins are crimped onto each labeled wire lead, it’s interesting to note that nuggets of gold scavenged from scrapped pins and computer connectors are able to be had on eBay for the purpose of recasting into jewelry or teeth or whatever else you’d like to make out of recycled gold.
Sausage casing time! The correct diameter of heat shrink for the section being wrapped is selected, and a heat gun is used to make everything permanent. Since each section or leg of the harness is worked on individually, you can still see incomplete sections formed with zip ties and needing to be spot tied/laced up.
Each labeled pin is the inserted into its corresponding lettered port in the circular connector. Being able to match your A’s, B’s and C’s becomes important during this step, but to make things more idiot-proof, circular connector manufacturers leave out letters in the alphabet that could possibly be confused with others. Notice that here, “I”,”O” and “Q” have been removed, good looking out, circular connector manufacturers!
Unused connector pin ports are plugged to ensure that absolutely nothing is able to enter. We’re talking to you, dusty powdered Bonneville salt that somehow ends up everywhere… It’s sort of amazing where you find the stuff at the end of a day on the lake bed, or maybe we just need to stop sagging our pants.
In order to add an additional layer of watertight insulating protection, self-fusing silicone “cherry tape” is wrapped around the end of the wire bundle, helping to create a tight seal inside of the connector base. This is a detail that will never be seen from the outside, but whose integration adds robustness to the harness.
Sealing the wire to connector junction from the outside, an adhesive lined 3:1 heat shrink wrap seals off the base of the connector. This is one more barrier that will prevent dirt, moisture and most importantly, salt, from entering the electrical system and corroding the wire harness from the inside out.
Sitting behind the screw cuff on this connector base is a wire ferrule which contains the wires and is heat shrinked to the harness, helping to provide strain relief once the screw cuff on connector base is tightened. The adhesive backed heat shrink, along with the cherry tape that was wrapped on the inside of the connector, provide an excellent seal for the wiring inside.
One connector down, now the process must be repeated for the 3 other larger main connectors that make up the harness. This particular connector is for the AEM AQ-1 data logger covered in a previous installment.
As you can see, building wire harnesses is one of Nick’s favorite parts of building a race car. Although, I guess his expression is about right, given that this photo was taken after two weeks of wiring harness boot camp mixed in with all the other parts of the car that have required Zombie Vampire attention.
In case field repairs should need to occur while out on the salt, a wiring schematic will need to be referenced. 5523 Motorsports’ Jen-Bot is hard at work here creating one of many pages that will accompany Project 240SX LSR out to Bonneville.
In another page from the NASA specification manual, the wire harness is then submitted to tug and chew durability testing from the shop dog, Zeus. He knows where to find the good stuff too, having developed a taste for unused tubes of DR25.
This completed harness is pretty extraordinary. I suppose that for such a critical part of the car, it’s only right that so much time and almost OCD levels of attention to detail were spent building it. And while the final product is certainly impressive in appearance, it is difficult to fathom the countless hours of planning, measuring, mocking-up, spot-tying/lacing, trimming, crimping, pinning, wrapping, and heat-shrinking it took to get to this point. Great job 5523 Motorsports!