If you use a move that has a type supereffective to your pokemon's type, if it has recoil will it be more HP taken?
http://pokemondb.net/pokebase/53860/how-do-i-know-how-much-i-will-get-hit-by-recoil Trachy's answer should help a bit. If you use Flare Blitz on a Parasect and it faints and it's HP is 300 the recoil damage will be 100 If you use Flare Blitz on a Wailord and the damage is 30 the recoil will be 10. The super effectiveness of an attack does not determine the recoil damage. Only the damage itself does.
Well recoil is a portion of how much damage is given, this varies by move, so the more damage you make the more damage you take.
Hope this helps