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efi harness


Toying with the idea of FI on my 66. I have the original harness I took out of the donor car. I have done some research and some are using the FRPP harness. I was reading on this harness though and somebody said its just a 93 replacement type harness that you will still have to modify. Is that correct? I am trying to get around having to build my own harness. Any other thoughts are appreciated.


Active Member

There's great website support for making/modifying an OEM harness work, however, it is a IMO a lot of work. I used Ryans (RJM technologies) harness and it doesn't get much simpler than this. IIRC, there were 4 wires that had to be connected to the car.... 12v constant, 12v switched, and a couple wires run for an inertia switch.... everything else was simple "plug n play".

After having gone through the initial apprehension of converting a classic Mustang over to EFI, I have absolutely no regrets and can't believe I didn't do it sooner. The engine runs (IMO) so much better with EFI than old carbuerator technology. Gas mileage ain't too shabby either!