UPDATE PINNED] How to play PS3 games from Vimm's Lair (jb folder to iso for multiman) tutorial - YouTube
Backing Up PS1/PS2/PS3 Disks Into ISO's multiMAN! (USB) - YouTube
EP 4) Running PS3 Games from an External Hard Drive (NTFS/FAT32) - YouTube
PS3 - I cant run games from hdd | PSX-Place
How to copy more than 4Gb files in fat 32 format (for PS3 only) - YouTube
MultiMan can read NTFS formatted drives connected to your jailbroken PS3 as shown in the linked video so you don't need to split huge games in FAT32 drives and merge them again.
How To Play PS3 ISO Games Off USB/HDD! (multiMAN) - YouTube