Forum » Practical Harness Construction - Club Level » OEM Connectors for Ford Focus Rally Car

OEM Connectors for Ford Focus Rally Car

Practical Harness Construction - Club Level

Discussion and questions related to the course Practical Harness Construction - Club Level

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I am building a harness for my 2003 Focus Rally Car with a 2.5l Duratec engine swap from a 2015 Ford Fusion. I am having a lot of trouble finding connector bodies or pins for any of the stock connectors. I am only seeing pigtails being sold, and I even checked the official motorcraft connector guide from another thread on this forum and they only specify pigtails.

What should I do for my harness? I have considered:

1. Buying new pigtails and splicing them into my new harness.

2. I have found that weatherpack pins at least can mate up with the pins on the sensors and actuators. I was thinking about using those pins to connect up to the oem component, and then potting the internal area where the oem connector would go and putting a Raychem SCL boot around it and building a pigtail out to a Deutch DTM connector. I have seen this done for a few items in a harness, but it seems a bit much for every oem component being retained (which is most of it). I am worried about the extra space for the pigtail, and the need to prep spares before hand with this pigtail.


Both your options will work. You will have street car reliability using the pigtails, and high-end motorsport reliability using the potting method, although you may want to solder wires and pot instead of using terminals.

Nothing wrong with using pigtails to start and understand if / where you will have issues, then move onto potting them as needs are identified.

Okay, awesome. Thanks for the help. Also, for the potting approach what potting compound/adhesive would you recommend for doing that? I have heard good things about Resintech RT125, but it seems a bit spending. Is there any middle ground to keep it nearer to the club level?

In terms of price per oz, I think this is less expensive than RT-125, however the convenience of the mixing dispenser can't be discounted:

Here is RT-125 and the dispenser for less overall dollars:

Have a look for Hellerman V9500, or Raychem S1125. I've had excellent results from both, and to be honest couldnt tell them apart from RT125. Not saying they'll be cheaper, but a couple more options to look for.

Hey, i was wondering what the reasoning is why i'd want to solder to the terminals rather than using the terminals? How exactly would i do that? theyre recessed pretty far into the connector bodies and soldering them would be interesting, would i cut the housing away?

Any information on this?

If I couldn't reach the terminals to solder, I would not hesitate to cut away part of the housing. You will be potting all of that anyway.

My concern with using terminals then potting is that you may end up negating the spring pressure that allows the terminals to work correctly. You can certainly create more surface contact area with soldering. Normally we don't want to solder connections (crimping is preferred), but if it's encapsulated, then soldering is very robust.