Golf 3 gauges speedometer problem.

I connected the counters from Golf 3 to SimHub and the tachometer works fine, but I did not connect the temperature and fuel level (maybe someone knows how to control resistance-to-ground-controlled counters). My problem is that the Speedometer cannot be calibrated. I set the minimum speed to 20, maximum to 200 km/h, then the minimum and maximum signals. However, game speeds do not match those on gauges. How to calibrate them better?