Guild Wars 2

What is the maximum level difference of the items I put in the Mystic Forge and the item I get from the Mystic Forge? Could I (for example) add four level 40 items in the Mystic Forge and get a level 80 item back, or is there some sort of limit, over which the level difference can’t rise?

lv40 items= 40 / a bit better. No lol, no 80 as a result

A difference of about 5 levels is what you can reasonably expect.