Hello. I am in the midst of restoring my original purchase '81 F150 4x4 V8 (302). I have just had the engine re-manufactured. A long time ago I lost the EEC III computer and finding no viable replacement I instead replaced the distributor with a single wire MSD. I learned then that the Tach was run off of the EEC III unit. I've seen articles that describe using the green wire and grounding the black to get the tachometer working but they don't specifically reference the EEC III scenario. I am wondering if I can follow the directions presuming I can find the wires? Note I do not have an MSD ignition module though I might consider that if it restores my tach. Thank you for your consideration.

 

Welcome to FTE.
You may want to look over this post made the last few days.
https://www.ford-trucks.com/forums/1...ach-issue.html
He made a tach harness to by pass the trucks wiring & cluster and got the tach to work.

You may also want to check with MSD, their site to see how they hook a tach to that dist.
You said it is a single wire, I did not know MSD made one?
Where do the wire(s) hook up to?
Dave ----

 

You will have to get a tack adaptor from MSD to make the tach work.

 

The tach signal historically comes from the coil.