What speed does the safety car drive in F1 Grand Prix?

The safety cars being used is usually Mercedes or Audi, at what speed do they have to drive around the track in order to stay in front of those F1 cars?|||The safety cars are very quick but they are forced to run under 200 km/h so formula 1 cars can warm their tires easier and their engines will not blow up because of the heat (exept Mclaren Mercedes).|||I'd say around 170kph.|||I think they can go up to 200 kph, but it obviously depends on the circuit. They may not be F1 cars, and they do look slow compared to, but they're pretty quick cars!