Don't type ... SPEAK !!!
Instead of trying to type all kinds of stuff to each other,
it can be a lot easier to just talk to each other.
Software : Free teamspeak client
Server : ts43.gameservers.com:9141
Of course, just like with the typed chat channel, it has to be quiet on the voice channel to during races and Qualify. So enabling the push to talk is absolutely necessary !!!
The key you could use for that is the "Scroll Lock" a key mostly not used by any of us...
Second method to be silent is by using the "Mute Microphone"
button during races or qualify
And If you want to be sure nobody can disturb you, you can also press the "Mute "speakers/headphones" 
button too .
So thanks to the "TeamOLD & TeamSLO", we can use their teamspeak server
The Software kan be downloaden here..
We have been using it with a small number of racers now, and it is a nice way to learn from each other between the races.