I actually had a ton of trouble "daisy chaining" the two firepods like that. They would sync up for a minute but drop out constantly.
Strangely enough, and I may be the only person this has ever worked for, (a PreSonus tech told me that it WOULD NOT work), I hooked both firepods up separately and put the firewire out of each one into a separate input of my Firewire CardBus. I have a 2 port CardBus, and sent each Firepod into a different firewire port, and it worked magically. Not one problem recording 12+ simultaneous drum tracks.
But, Make sure you download the firmware updates from PreSonus before you try linking them together in any method!