With Oracle ASM 11g, the largest supported ASM disk size is 2 TB. Do not create ScaleIO volumes (or VMDKs) larger than this size for ASM 11g use.
For Oracle ASM 12c the largest ASM disk size is 32 PB.
The smallest ASM disk that ASM can handle is 4 MB.
For ASM 12c larger volume sizes may be used, but if using virtualized hosts, be aware that VMware has a maximum supported volume size of 64 TB for an RDM, and 62 TB for a VMDK disk.