EFI Wiring question - almost there!

I have a few things left to do before I'm finished with this project on my '66 Mustang coupe - I cannot wait!

There are four wires to splice in, but I'm not 100% sure where to splice them, could any EFI guys here help me out with this?

One wire is labeled "Power" that is pink w/a black stripe, a "Run" wire that is all red, a "Start" wire that is all Green, and I think this is the ground wire it's not labeled but it's Black with a light Blue stripe.

Power: run this on the + side of the starter relay? (the left side terminal?)
Start: run this on the 'S' side of starter relay?
Run: I dunno (maybe the right side terminal on starter relay?)
Ground (if it is a ground wire): run it to the body of the car?


Amazingly my 'I' on the starter relay was not hooked up before this conversion... the car did run fine too. Maybe because I have the smaller starter from a '92 mustang or so?

I'm also curious how and where I should run the wiring for the Inertia switch? I'm sure one is a ground wire to the body somewhere, and the other maybe to the + on the fuel pump?

Any info would be great! I've got ~ 24 easy tasks left before I can awaken her... just need to find the time now.

65conv50 said:

If I remember right: "Power", to a lead that has 12 v all the time that the ignition switch is on. "Run" to a connection that has power when running but not starting (the radio lead worked for me). I ran "start" from the starter lead on the ignition switch. And "ground" works best wired to the grounded lead of the battery, but a chassis ground is good, too..

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I'm sorry I'm a rookie when it comes to wiring. What did you use for "Power" ? I guess the right side terminal on the starter relay is not sufficient?

Is there a way to do the "Run" from the ignition switch as well?

65conv50 said:

Another point from my own experience. Run two good heavy ground straps from the engine block to the chassis rails (not the body). This is important. Mine blew out ignition modules until I did this.

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Will do!

yeloxr7 said:

That wire should go to the fuel pump relay, not directly to the computer.

Also it is a good idea to use a later-model starter solenoid. This is the one with the terminals on the end of the cylinder. It has a diode built into it that will protect the computer from power surges.

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I'll pick up a '93 starter solenoid and wire it up - thanks for that info! I'll take the extra precaution


Do you happen to have any diagrams on how to setup the inertia switch, fuel pump, and the relay? (what relay do I need?)