Some of the big car tracks here in Ohio that also run karts occasionally have been using racecievers to speed up alignments on the track and to warn drivers of accidents and such . On a small track they wouldn't be as helpful towards warnings , but would help with aligning drivers to where they belong . But using a similar device that can be only used between the driver and a crew chief is forbidden , that is where the hand signals came into play . When 2 people can communicate directly with each other , the one on the sidelines can let the driver know that he is going to get passed on the outside as an example , which the driver could possibly change his line to block , which is very unsportsman like . That is why most sanctioning bodies don't allow 2 way communication .