[Grady Clay]

John,

Re: Porsche 901.602.601.00 “Ballast unit for transistor tachometer (BHKZ)” Vorschaltgerat fur Transistor – Drehzahlmesser (BHKZ).

The Porsche (paper) parts manual and wiring diagrams show that change (delete this part) beginning with the ’71 model in 9/70. That has been my experience also.

The ’70 911E tach 901.741.302.04 uses the “ballast.”
The ’71 911E tach 911.641.302.01 does not use it.
Similar for the other tachometers.

I don’t think the later tach will work with regular Kettering ignition.

Best,
Grady