Can the VAG-Com work with 90-91 20V cars? What can I expect from such a hook-up if it is possible? Can I reprogram the computer on these cars?

Someone brought a 20V non-turbo of that vintage by here not that long ago and it worked, but at some totally wonky baud rate that we wouldn't have picked up with a dumb interface. However, there wasn't much data to be had from the car.

20V Turbos of that vintage definitely work.

-Uwe-