My c230k has a limiter fitted, this has two functions, it can be set to permanently restrict the top speed (ie it doesn't have to be reset each time you drive) this can be set between 120mph and 145mph it also has a temporary limiter which can be set on the move and adjusted or switched off. Mine is a year 2000 model and the speed at which it is limited on the temp. function comes up in the odometer display, not sure if other model years are the same.