Hello,
I have tested this in multiplayer and it’s working fine.
However, some things must be adjusted for MP like car siren, lights, nitro (event on server).
Also, this is very good vehicle system (physics and control) but it has one drawback. It uses event tick almost for everything which can drastically affect performance, specially in multiplayer.
I moved some tick events into custom events, but it still lot’s of work to get it better. Collisions are not perfect and for some reason the car sinks from the landscape (usually on high speed hits).