HD for E4K?

I would like to install a larger HD inside my E4K than the factory-fitted 270Mb unit.
I assume it has to be a SCSI HD, but what's the largest HD size the E4K can read, or does it not matter?
Thanks,
Gilles
I assume it has to be a SCSI HD, but what's the largest HD size the E4K can read, or does it not matter?
Thanks,
Gilles