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Bronco I bought had a GM HEI distributor put in place of the stock. Previous owner didn't replace tach cable. Instrument panel and circuit board are in good shape.

Any recommendations on Tach cable to buy and how to hook it up would be greatly appreciated!

Thank you.
 

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Hi Jolene,
What engine do you have in the Bronco?

The stock wiring harness should still have a wire for the tach. It just might not be hooked up.
It's simple to do though. It just needs to run to the Coil (-) on the HEI. It's on the left side of the two wires on the cap.
There should be a green and a red one. Red is Coil (+) for power, and green is Coil (-) for the tachometer.

It just needs to be connected to your tach wire.
 

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85 Bronco, 309ci I6 w/4bbl, np435, 4" lift, 37" Irok NDs, 4.56 w/ Detroit Locker and tru trac
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If that doesnt work, you have a bit of work to do. You'll have to determine the plug location on the cluster for the tach wire, then run a wire from that, to the HEI.

I have a partial map of the printed circuit board from my 85. It doesnt have a tach, so I can tell you which ones arent going to be the tach wire. Lemme know if you need it.
 

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If it already has the printed circuit, that's 90% of the way there. The nice thing is, the wiring harness has the wiring for the tachometer whether or not it originally came with one.

When I first got my '81, it didn't have a tach. I just put in a cluster with a tach and it instantly worked. There was no rewiring of any kind involved.

So, if nothing else, it'd just be a matter of locating the wire in the engine bay and hooking it up to the HEI. It's either hanging loose somewhere, tied off, or cut. Either way, it should just be a matter of running the wire.

As seen here, it's a wire that comes out of the ignition module. Mine have always been green, so I don't think that changed throughout the years / engines.

Now, if the Bronco also has an aftermarket ignition, then that complicates things slightly.

154068
 
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