The analog speedo is not accurate.
With my CS, I have tested 6,000 RPM in fifth and I have seen:
270 km/h (167.8 mph) with the analog,
264 km/h (164 mph) with the digital.
The final drive ratio is shorter on CS than S4, especially automatic.
The previous owner told me that is record is:
300 km/h (186.4 mph) with the analog,
288 km/h (179 mph) with the digital.
I believe this as it matches the ratio diagram of my car.
288 would match with 6,550 RPM.
I would like to check this during the Euro in September.
Don't want to remove the right mirror but have no radio, nor antenna.
'89 CS, with digital dash