Balancing index data flow

Hello,

i have an enterprise level indexing environment for file searching. I'm currently working through the whole file system backlog and disk space has started to become an issue...so I have some new nodes I have kicked up that I would like to add to this cluster to allow enough collective data storage to complete this initial indexing backlog, but since space is at a premium I would like and try to balance and level out the data between the new nodes while allowing enough headroom for organic growth of the file system. Is there a way to do this?