@nomaishere
In terms of it being possible in the standard versions of the Engine? I don’t think so, there’s probably a hard-code of the maximum file size for partitions in the Source, so anything that changes that should be done in the deeper files.
If you were to manipulate this value I think it would be possible, but you’d be opening yourself up to performance issues on both the graphics end as well as storage space with the larger maps, so I can’t fully recommend it, but if that’s not an issue, it could be worth a try.
I also found a pretty in-depth post about it from a little while back. Maybe it could shed some insight on other possibilities?
I hope this can help!
-Zen