In multiplayer, I have a similar issue with stock FGear assets:
Place 100 stock FGear BP like the Arcade car in a row, side by side.
Possess the first car and start driving towards the end of the row (that you can see)
Try to park at the end of the row. You’ll hit some thing invisible.
Try to park slightly further at the end of the row… same thing.
Un-Possess vehicle. All of a sudden you can see that you were actually hitting other vehicles that just refuse to pop into view.
Doesn’t happen in single player.
Also car to car interaction is MUCH better in single player than in multiplayer. In multiplayer cars don’t really want to interact.
We also ran into a problem, where we “sleep” vehicles not in use by disabling physics and tick, and enabling them when possessed. This causes you not being able to move in multiplayer and the log getting spammed. I fixed this by modifying FGearReplication.cpp:
From:
mVehicle->SetActorLocationAndRotation(pos, rot, false, nullptr, ETeleportType::None);
To:
mVehicle->SetActorLocationAndRotation(pos, rot, false, nullptr, ETeleportType::TeleportPhysics);