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A mustang wiring guide for an overly ambitious weekend mechanic

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Howdy ya'll! I'm putting together a wiring guide for those crazy enough to want to wire their own car. My plan is to link to my wiring file and include all the detailed info you need to get started /understand the scope. Would love your feedback as I am working on it. Here's a link to the guide Honey Badger Wiring.xlsx. I plan to share videos once I get done editing.

Copying the first sheet below for feedback. What am I missing? What other questions do you have? I should probably add a section on sourcing OEM connectors

A mustang wiring guide for an overly-ambitious weekend mechanic
: In this document, I want to share the info I learned while installing a full standalone ECU and PDM in my race car. This should help answer those questions you have during your research phase and give you a good starting point in your own planning. I don't plan to provide guidance on how to crimp or design your own harness as I am not an expert and that's best left to those like HP Academy.

Skillz acquisition: I bought the HP Academy courses on wiring (suggest their unlimited subscription if it fits into the budget. There's so much to learn on that platform and they're excellent teachers. Otherwise youtube!

Cost: Total cost was between 8-20k depending on tools bought and choices made with the electronics. A basic AIM PDM/Link ECU combo with their wire looms and stock connectors could be done for about 8k. Subtract 4k for reusing stock chassis wiring and fuse box. On the higher end, you're looking at 16-17k for Motec stuff + wiring. There's a ton of variability here. For wiring itself, I ended up making a lot of my own harness using Tefzel wiring and switching to some autosport connectors, so I added a good bit in tooling and materials. For reference, I probably spent about 12k on my build. I was quoted a minimum of 12k for professional engine and chassis harnesses (basic materials), so I'll consider this a win.

Mustang/Coyote Considerations with standalone:

Coils: The OEM coyote ignition coils are ""dumb"" coils, meaning the OEM system includes an ignitor to help with spark (it's not stored in the coil and then a trigger giving to release it). Motorsport ECUs require smart coils, so you'll need to either wire in ignitors or convert to smart coils. Ignitors will allow you to retain the OEM coils, but the ignitors fail, you're stuck unless you have a pair. Converting to smart coils only requires adding a ground to each coil on the wiring side, so I went this route. I then use R35 GTR coils, which are good to 2k horsepower. This way I can buy replacements at any nissan dealer. You'll need a kit like this to run smart coils on a coyote https://www.platinumracingproducts....s-ford-coyote-coil-kit?variant=42588782952680

EPAS: The Ford OEM electronic steering unit requires a CAN signal to operate, so you'll need to buy a simulator kit from Cortex that turns it into a standalone or wire your PDM to it to control it.

Sensors: All of the OEM sensors will work with the ECU, but you won't have an oil temp as the OEM ecu uses a math formula to calculate. I suggest changing the OEM sensor to a pressure/temperature combined sensor so you have both pressure and temperature. Links to recommend sensors are in a later tab. Most will want you to convert to MAP from the factory MAF, so I suggest buying a MAP sensor - this is superior and gives the ECU better data to work with.

VVT: Cam control won't be available for all cams on all standalone ECUs, so make sure yours supports it. You'll need to use 4 outputs to control the solenoids and utilize 4 inputs for the angle sensors.

ABS: if you're reusing OEM ABS, you'll need to give it info over the CANbus. Unless you're experienced in this area, this will be a fairly large headache. I suggest switching to a standalone system like the Bosch M5 motorsport ABS or the FP350S unit.

Alternator: The OEM alt will work on its own with nothing plugged in but the 12v battery cable. However, most ECUs will have the option to control the ALT under certain engine loads and the ALT has this ability. So I suggest sending at least one wire to it for regulatory control.

PDM install considerations:

A full race-car wiring job will require at least 25 outputs, so choose your PDM accordingly.

Your PDM will need to supply power to some engine-related controls - the coils, injectors, and VVT solenoids all run off of 12v. If your engine harness also hooks up to your starter, you'll also need to include a starter solenoid output. I also wired my EPAS power to the same output as the VVT.

Tools and materials:

I buy all my materials and tools from ProWire. Cheapest and best selection. Seriously, don't go anywhere else.

In regards to tooling - I started out with the cheaper tooling, using knock-off Deutsch and barrel crimping tools. They sucked and led to unreliable crimps. If you take your time, are super meticulous, and the budget allows, I HIGHLY suggest buying the real tooling. It's literally idiot proof and turns a frustrating job into a fun job. It's worth every penny, IMHO. And resale value is good if you want to get rid of them. Seriously, I can't recommend the good tooling enough. If you're able, buy the good stuff. If you like nice tools, buy the good stuff.

For most of the OEM crimp connectors (injectors, coils, sensors, etc.) - Aptiv 15359996

For Deutsch connectors: DMC AF8 M22520/1-01 (I bought pre-owned from ProWire) with DMC TH1A TURRET

For Deutsch Autsport connectors: AFM8 M22520/2-01 (turret will depend on the terminal/connector you're using

For ring terminals: Sargent 3125-CT has worked well for me

For open barrel splices: Sargent 3187-CT has worked well for me

Wire stripping: For tefzel, you'll need something like IDEAL STRIPMATER TEFZEL STRIPPER 45-1987. Tefzel wire really needs its specific stripper. I used a generic one earlier and it worked okay, but it broke some strands, which can make the crimp fail






Man I was smiling until I got reality-checked by the cost estimates :eek::eek::eek:
there's definitely no way to really justify the cost. It's depressingly expensive - even on the cheap end. My PDM/dash combo was 3500 and my ECU was 2k. Add in another 1500 for my flying lead harnesses. And I didn't even go crazy - Link ECU and AIM PDM are relatively affordable. A Motec setup is like 10k without any harness stuff.

I will say - the flexibility is wonderful tho
This project looks to be above my confidence level. Interesting project, but I hope I don't ever have to rewire one myself.
it's not as bad as it looks once you break it down and get started. i'd say anyone comfortable doing their own fab work or electronics work is more than capable. I learned everything on YT and HPA - no prior wiring experience other than zapping myself trying to change out outlets in my house.


Because racecar.
Arizona, USA
That is a really good expectations-management and informative post, btw. Thank you for taking the time to document that. I have been contemplating some of this stuff as a "what if" at some point in the future, but clearly I didn't understand the scope or scale of what needs to be done.

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