LS engine wire harness clean-up

An LS engine wire harness clean-up is something that should be considered if you plan to swap one of these engines into your older car. The appearance of the coil brackets, fuel injectors, and the associated LS engine wire harness is a very common complaint that many people have about the LS engine.  Some have chosen to hide the coils, remove the coil brackets, cover the injectors and associated wires. I have chosen to keep the coils, brackets, injectors and wire harness in the stock locations. Regardless of which option you choose for your LS engine, it is a very distinct looking machine and the factory stuff needs a little sprucing up!

Recently, I modified the coil brackets and had them powder coated at Gateway Powder Coating in an attempt to clean-up the coil installation (see: “Gateway Powder Coating – LS engine coil brackets“). This was a success, but the LS engine wire harness needed attention now. I contacted Dwight Van Lake at Whitmor Wirenetics for an aerospace style, LS engine wire harness clean-up solution.

coil bracket thread thru
The modified coil bracket is mounted to the valve cover with the coils and coil wire harness installed. The coil wire harness now passes through the modified bracket which makes for cleaner edge.

Whitmor Wirenetics is a manufacturer and distributor of MIL Spec. quality wires, cables and various tubing products. I was initially drawn to them for their extensive heat shrink and booting selection. If I had not already purchased an aftermarket wire harness (more on that in the future), I would have used many of the wire bundle boots they have to offer. The boots are expanded heat shrink material that offer maximum security, safety, and strain relief of the wire bundles at the break out points; plus they just look cool. Whitmor Wirenetics also has a very large selection of straight heat shrink tubing of various sizes and shrink rates. I have used similar materials in the past on aircraft wire bundles, but was not able to obtain any for personal use.

Now having found Whitmor Wirenetics, I purchased the straight shrink tube (part # WS5034-1.5-0) that is a 4 to 1 shrink ratio and measures 3.5 inch in expanded form and, after heated, will shrink to approximately 1/4  inch. This shrink material was used on the main coil harness connectors, as well as on the injector harness, coil plugs, and other sensors on the motor. The result is a plug boot that encompasses the plug, wires leading into the plug, and any protective braiding around the wires. This newly formed boot acts as another protective layer, a mechanical support for the wire bundle, and a cosmetic finish that is nicer than a multi-colored group of wires terminating at a plug. Also you need a type of adhesive tape to keep things in place as you shrink the tubing; I used HMT200A as suggested by Dwight.

Follow along with the pictures and captions to learn how I accomplished this simple clean-up technique.

In this photo, the injector has the braiding kept on with a small zip tie. The zip tie is cut and removed. The 1st part of the booting technique is to peel back the braiding (if you have it) and wrap the wires with HMT200A adhesive tape. The HMT200A adhesive tape will require a quick flash of heat from the heat gun to activate it.
Once the HMT200A adhesive tape is wrapped around the wires, the braiding was positioned over the HMT200A and another layer of HMT200A is wrapped around the braiding and heated. Essentially, this is making a sandwich of materials. This “sandwich” will keep the wires adhered to the brading and the shrink tube adhered to the top layer of HMT200A adhesive tape. Seen here is the sandwich of HMT200A with the braiding ready for shrink tube. Before I cut the shrink tubing, I measured approximately 1.9 inch of area needed to be covered
plug preshink
The 4 to 1 shrink tube was measured and cut at 1.9 inch and positioned over the plug. It should be noted that before heating the shrink tube, the both male and female plugs need to be connected. If the plugs are not connected, the shrink tube will cover the weather seal on the plug – you don’t want that.
plug after shrk
After the plugs were connected and the shrink tube heated, this is the boot that is formed. Also seen here is a comparison between a boot on the upper plug and no boot on the lower plug. In my opinion, the upper plug with the boot appears simple and clean in design.
LS engine wire harness clean-up
When finished, the boots really tie everything together.
From this perspective, the boots over the plugs line up and allow for a better level of organization. Also, the color of the shrink tube matches other design features I am incorporating into the build.

My goal was to clean-up the LS engine coil brackets and associated wires on top of the engine while keeping things as maintenance friendly as possible. The newly formed heat shrink boots over the plugs will match many of the design qualities already present in this build. While there are many ways to clean up a wire harness, this method was my simple solution.

Keep checking back for a very big development with the LSX El Camino! Old school meets new school with a punch!

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