Wheel Speed Sensor to Speedometer Signal

[scootermcrad]

I'm looking for a solution to run a 964 speedometer without the use of the ABS unit. I have found one useful thread on the subject over on the 964/993 forum that had the start of some very useful information, but it's an old thread and seems to have stalled, so I thought I would bring the topic back up to the surface.

There original thread...
https://forums.pelicanparts.com/porsche-964-993-technical-forum/582770-964-speedo-signal-abs-sensor.html

With all the engine swapping going on, these days, I thought it might be a good place to bring it back up over here for more general conversation.

So the question that I need answered, is:

Can the 964 wheel speed/ABS sensor, located on the left front wheel, communicate with a 964 speedometer using only the FCU module, or is there another translation that must occur within the 964 ABS unit? This seems like a simple translation of one square wave pattern to another, but I can't seem to find a definitive answer. If the ABS unit IS required, is there a way to emulate what it's doing using another method? Maybe an adaptive microprocessing unit of some kind?

The FCU module for my particular situation (1991+ C4 G64) I believe to be 964.618.220.00

If anyone has knowledge of this and maybe even a rough diagram (chicken scratch napkin sketch counts), that would be helpful.

Thanks all!