New E-tec

[dpo1951]

I just replaced a 2005 60HP Mercury with a 2018 (90 E-Tec on a Nitro 640 LX 16' 4" boat. Took it out this morning and was disappointed to find that I got the exact same speed out of it that I did with the 60. It has a 19 pitch prop. At 5500 rpm I get 40MPH GPS. WOT puts the RPM,s at 6000. My dealership says that is OK but the manual says max 5500. Should I be able to expect more from this engine? Would it be a setup issue or is that what I can expect? Thanks.

[boats.net]

That engine has an operating range of 4500-5500 rpm's. If it's turning 6000 rpm's at wot then try a 21 pitch prop. That should increase speed a couple of mph and decrease rpm's at wot.