My new skiff came with a Mercury Spitfire 4 blade 19 prop. I am only able to turn 4700-4900 rpm's even when I am light on fuel and gear. I have yet to see 5000 rpms. I was hoping there were others out there that have the same set up and were dialed in a prop that will allow for the correct rpm's of up to 6300. Thoughts would be appreciated!