Re: Propeller Question for 60hp EFI mercury
I just wanted to add that I have a similar setup as you, except mine is a 16' Triton bass boat with a 60HP merc, I changed my prop from a 13P mercury aluminum to a Turning Point Hustler 15P aluminum, and my speeds went from 31-32 up to 38 fully loaded (about 1500lbs with me in it)....made a big difference, puts my WOT RPM's to 5200. I don't know about your 4 stroke, but my 60HP is a 2 stroke year 2004 (ELPTO) and 6000 RPM's is past the redline on it per Mercury. You may be pushing yours too hard, meaning you need to add some pitch. You never mentioned which prop you are using...more specifically what dia and pitch. My guess is you might be a little under-propped....then again, perhaps the 4 stroke version of the 60HP uses a higher redline, but I would be nervous pushing my motor to 6000 RPM's. When I was using the 13P I was getting 5800RPM's at WOT....too much rotation, not enough speed. Cost me $70 for the new prop (with hub) and I am much happier with the higher speeds and lower RPM's.
I also wanted to 2nd the notion that you will not be likely to hit 45MPH with that setup...no matter what prop. If you go up a pitch or two, you will bring your RPM's down and likely your speed up...but probably only 1-2 MPH. I just think your RPM's are too high, especially if this is where to tend to cruise.