Welcome to BoatMad Oscar!!
i guess you mean "improve" not "remove"
i'm pretty sure your 2.5 should have a higher rpm
a lot can change by the height your engine is mounted at, mid-section used (20"/15"), how far it's usually tilted,
changing some of these could gain much more revs with the same prop,
also depends on what kind of water you run in,
put some more spec of the boat and the way it's set up on here and i'm sure many members will be able to help as it's a very popular boat and engine.
Hope BoatMad can help,