I've used the sealing splices on mcmaster and they're every bit as good as the crazy expensive MIL ones I have. If I hadn't gotten my MIL ones from work I'd have never used them - they're cool, but literally the same as some of the ones McMaster sells.
Another supplies shipment arrived:
Raychem boots for the milspec connectors:
Left to right - Heat shrink for adding drain wire to shielded wire, Kapton tape, Kevlar lacing:
This stuff is for re-work...as in I'm re-doing the Autosport AS and ASL connectors:
Closer look at the heat shrink tubes for shielded wire:
800ft more Tefzel wire:
New tools:
AFM8 crimper and 20awg positioner:
Comparison with the AF8:
The Cadillac of wire strippers, the Ideal Industries Stripmaster Ergo Elite:
They have a composite frame, so it's super light in the hand:
Wire length stopper installed:
OOOH. I've never seen that wire length stopper before! I gotta get me one of those!
The Ergo Elite stripper is so much better than any stripper I've ever used, it's just ridiculous.
--Peter
I know you two (Adam and Jon) have done plenty of electrical work.
So, obviously I'm asking because I don't know, these are the best style butt connectors?
I realize $700 is a lot. I'm just wanting to you know. Having said that, this is recommended over soldering and heat shrink?
This is my signature....
Peter,
It's got some benefits and drawbacks.
Yes you can set the length, but it blocks your view of the slots. After some practice you do get a feel for where you place the wire, but it takes some practice.
I've only used it for 2 days...but I think it's fast becoming my favourite tool in the box! Super nice piece!
The AFM8 is a lot easier to use than the AF8 for 20awg as well. I think I did over 100 pins today with it...
In a vibration environment, crimping is preferred over soldering. (Assuming both are performed properly) As long as the solder joint is properly performed, it should be fine for the life of the average car. On an F1 engine though, which is where most of these snazzy Autosport connectors originate, vibration has killed connections....
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Building the Power Interconnect harness to bring power from the PDM to the driver's side of the engine bay. (Where the M150 ECU is)
The harness has 8 runs of 12 awg wire, and the yellow "string" around the bundle to keep it tight is Kevlar lace:
Not everything goes to plan. In the image below, you can see how I cut off a $20 Raychem boot because I messed up the shrink installation:
My mistake was installing it full length. In the image below you can see the trimmed boot on the right ready to be applied to the connector:
Nobody has ever mentioned this before, so I thought it would be useful for others to learn from.
Boot installed on the Power Interconnect harness connector:
That was yesterday's progress.
Pei! You have done everything sofar apart from the full on rewiring that I had planned on!! Haha level of jealousy right now is immense! I cannot wait to hear this thing scream! It's funny I stumbled upon this thread while looking for references and ideas.
Been following you 2000_328ci- chase and a few others but had some things come up and started another build and find great inspiration from you all!!
devin
Thanks guys!
Continuing on, below shows the construction of what I call the "Interconnect" harness:
I'm using a method called Concentric twisting to layer the wires in a flexible cluster. The 2nd layer completed:
Wrapping the 3rd layer:
Wrapped with Kevlar lacing:
Setting up to apply 3/4" heat shrink:
Raychem boot applied to connector:
Test fitting on the car:
The purpose of the 39 pin "Interconnect" harness is to transfer signals between the left and right side of the engine bay. This includes 3 CAN bus lines, and various other I/Os.
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The next harness I started was the "Ignition" harness. Below I'm populating the 32 pin connector utilizing the pin insertion tool provided with the connector:
A little bit further along in the process:
Resealed OEM ignition coil section:
Connector and transitions:
Aside from the ignition coil signals, this harness also has connections for the Racegrade TC-8, Motec LTC, and what's called the CJC-1 for the E888. . This CJC (Short for Cold Junction Compensation) is a temp sensor that is positioned close to thermocouples connected to the E888. This used to establish the ambient temp baseline, and then the E888 corrects the the thermocouple measurements.
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Completed Ignition Coil harness:
Constructing the harness that runs from the center console to the "drug bin":
And that's as far as I got with that, I need more 1/2" heat shrink.
I've also started the left side engine harness (41 pin connector is full of pins), but I don't have any pictures of that yet.
Beautiful work, Adam. Puts my twisting to absolute shame!
--Peter
WOW the work is top notch (always has been)
quick question, when you were drag racing the 330 way back with the 330i rear brakes what was your wheel setup in the rear?
Great work Adam! Thats a cool way to make a harness with the wires wrapped like that. Never seen it done like that before.
I like reading your threads and learning new things!
They are all signal wires.
For signals that I'd like to shield, I have mil-spec shielded wire as well. (M27500)
Thanks Nick
The primary benefit to twisting wire bundles like this is flexibility; the wires move more sideways instead of in compression and tension.
The secondary benefit is that the layup is compact.
And a third benefit is that it looks really cool....
To be clear guys, this is not my profession. I draw inspiration (and instruction) from the real professionals at Apex Speed Technology.
Adam -
While that looks cool and Apex may do that, I cannot find any reference to doing anything like that in a MIL specification. In fact, the only twist that I have ever seen referenced is specific to TPI for noise reduction. I am worried that your wires being spiraled around like that is going to make for issues with high frequency noise in addition to the fact that your cabling is unnecessarily long as such. If you wanted to get a clamp on there or use a pierce for oscilloscope or volt meter/logic analyzer, you're going to have a hell of a time find the wire.
Last edited by 5mall5nail5; 03-29-2015 at 05:01 PM.
Jon:
This method of concentric twisting is absolutely standard for all autosport harnesses. It adds strength, flexibility and noise resistance. No doubt that it makes finding a wire that you want to clamp hard to find and reach. But if you look at every Sakata, Apex, Motec or other harness, they all use this technique. I'll see if I can dig up some of the resources that describe why this is done and how to do it.
--Peter
PS: Here's a good starter link: https://www.rbracing-rsr.com/wiring_ecu.html
Last edited by herrubermensch; 03-29-2015 at 05:48 PM.
Interesting thanks Peter. I would just be very careful what you're wrapping the wires around. Wrapping wires is in fact a long-used method for noise cancellation but you have to be very careful what the noise you're trying to cancel is. Wrapping all your low level signals around a high current source may not be ideal.
Jon,
I suggest you try this out and see how you like the feel of the bundle. There is a difference.
As far as any noise issue goes, I'm using Motec which comes with Elf Level - 14 protection against this.
Adam my harness is wrapped but in twists on signal wires. Its compact still but a little different. If you have some sort of active protection against noise I suppose that'd work, but 5vref signals do not have a whole lot of amplitude and can be exceptionally vulnerable to noise. I am sure you've prepared for that though it looks cool.
Looks like you're taking to it like a fish takes to water, Adam! Nice work as always.
For anyone on instagram interested in seeing more super impressive wiring skills, check out @RACESPEC. He does "motorsport wiring" and "motec installation" work. Very cool stuff/pics to look at.
On a non-wiring related note, I assembled this contraption to test boost lines and the solenoids:
Sometimes I just like to prove things work...
Very useful! I turned a PVC cap on a lathe to get it the right diameter for my turbo inlet. I used a silicone coupler to attach the PVC cap to the turbo inlet, drilled an NPT hole in the cap, and pressurize it just like you are from my air compressor w/ a gauge so I can watch boost "leakdown". Very useful stuffs.
Jon,
Your comments did not sit well with me, so I've taken some time to reflect and reply in a constructive manor.
There are many "directions" one can follow including specifications, documented industry best practice guidelines, and guidance from industry professionals. In general, I tend to pursue all 3, and balance their application based on my own tool and skill set.
There are no MIL specifications for concentric twisting because that is not the purpose of MIL specifications by design. Concentric twisting would part of a work order, work instruction, or as part of a Quality Specification guideline. MIL specifications define how a part is constructed, not how the assembly of those parts is performed.
Harnware is the wiring industry's benchmark design and construction software from TE. As part of it's "Help" documentation, it lists best practice for many types of harness construction steps. Below is a link to the document for Hand Cable Laying, as part of their Harness Assembly Instructions:
http://www.te.com/commerce/DocumentD...=SS&DocLang=EN
This is an example of industry best practice.
Lastly, I have been lucky to spend a fair amount of time in a number of professional automotive racing environments. This gave the opportunity to see first hand how wiring harnesses were constructed and utilized in some really nasty user environments. I've seen the innards of quite a few harnesses; some because they were torn apart due to crash damage, some due to maintenance damage, and some due to fire damage. All of the top race teams seemed to share common wiring harness practices, including concentric twisting. One such example was Penske Racing with the now retired Porsche LMP2 car. They had electrical gremlins, so harnesses were being cut open in the pits to try understand what was happening out the track. I saw those harnesses, which were built by Porsche Motorsport.
This is an example of professional experience.
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