I have a 2003 440 fan Pro X that I plan to swap with a 550 from a 1999 supersport. The 440 is toast and I found a running 550 for cheap. But, I noticed that the carbs are bigger on my 440 than the 550? Has anyone ever messed around with the larger carbs on the 550? Jetting? Also, I was curious about running the primary clutch(white spring) of the 440 for better launch? Experience/thoughts?