I know in Beamng there are already fires but a real fire with consuming cars and transmissible fire where pretty cool . I don't know if this is workable and if this is hard to work ?
I'm no tech genius, but it may be hard to render. if the car explodes, it would have to work similar to the way the broken glass texture is triggered, so basically it would have to happen quickly, but if it was just on fire then maybe they could make a burnt texture slowly fade into the mesh? Like I said I'm not the sharpest when it comes to coding and stuff, and I don't really know how the meshes work, but it may not be easy for them to do.