I have a 07 285 with a vmax 150 carbed motor. I am getting about 58mph wot at 5900 rpms. In the manuel I think max rpms are around 5500. I want to add a jackplate, I was wondering if I need to go to a bigger prop. I am running a 23m now and was thinking of going to a 25p tempest, that should bring my rpms down to near 5500 right? I dont want to put that much $$ if it isnt going to be right. thanks for the help