not much...but your car would be pretty happy im' sure!
teh fmic really isnt gaining you much power, its just letting you keep your HP at max during hot weather and back to back runs.
the tunes are what really pulls the large amounts of HP out of the mods.
oh, and paying for those mods and not spending the $$ on a tune makes no sense.
you are already modding to the point where a dealer could throw your warranty out the window if they wanted to.