Is vehicle non-collision (e.g. ghost mode) possible?

Issue

Just a quick question, got some friends wondering if its possible for us to disable collisions between vehicles for races/hot laps etc

Yeah sure that is a game own feature called Simplified Physics. You can find it when you go into the Settings → Gameplay → Scroll to the very bottom. You can also additionally enable the vehicle fading option under Settings → Multiplayer. This fades out cars the closer they get.