Lingenfelter uses the LSA ZR1 cam,
http://www.lingenfelter.com/mm5/merc...gory_Code=C461
700HP KIT -
http://www.lingenfelter.com/mm5/merc...=#.UsLDzoko5Ms
As I read through the tech articles though, looks like the 650 kit from Lingenfelter could get it done w/o breaking into the engine: if a full exhaust was added, possibly right near 700 flywheel hp would be obtainable.
http://www.lingenfelter.com/mm5/merc...=#.UsLD9Yko5Ms