Magnum swap-what all mods can you make still using factory efi

I am trying to find out what all mods/performance improvements can be made to the magnum motor and still retain factory efi. So far I have found the edelbrock/hughes intake, different heads such as EQ, but my concern is once you start going to a more aggressive camshaft (not a particular camshaft in mind) will the factory computer compensate for it? Can these be reflashed or a tuner used? Just wondering how much flexibility is there to retain the factory efi.
I have looked on this site as well as a bunch of the dakota sites as well but I didn't really see the answer to the mods I am looking at.