Mechanical to Electronic Tach swap ?

[Naplesworkshops]

I searched on this topic but found nothing...

Here is my dilema: I swapped a '79 engine into my '77 spider forgetting that Alfa switched to an electronic tach in '79. Now i am stuck with trying to swap the electronic tach from the '79 to the '77. Does anyone know where the white wire connects to ? I am assuming that this is the wire that picks up the signal from the coil ? The '79 wiring diagram doesnt show this wire (of course).

Thanks in advance.

[ghnl]

I think the tach pick up - "the white wire" - would go to the coil + terminal. See if you can wake up PapaJam, I know he'd know.

[Naplesworkshops]

Quote:

Originally Posted by ghnl I think the tach pick up - "the white wire" - would go to the coil + terminal. See if you can wake up PapaJam, I know he'd know.

[papajam]

I'm awake, I'm awake!

Two thoughts;
1) install the 79 tach and hook the white wire to ignition coil negative
2) retain the original tach; install the 77 mechanical tach drive into 79 waterpump