Can u show me where in config I can disable client side by default on server?

"For PVP, you can stop the mod from functioning on your client side."

You can't disable client side through config from server side.
There is a button on the GUI for the client itself to disable the function on a per client basis.
You can use other management mods to force disconnect clients with CAR installed.
However, assuming you still want your players have CAR in normal situation, it is possible to develop an addon mod that interacts with the API provided by CAR to achieve your goal.