Might be. I know tip speed is a big contributor to quality of cut.
I modded my 48SD with the smaller pulleys from a 42 and I cut the chute back to just outside the track of the right side blade. That deck mows like none of my other 42 or 48 decks. It is a beast! I mow at about 3/4 throttle and it never bogs down. And it slings clippings much better as well.