I have a 17' 1986 Vector with a 2002 Johnson 115 engine on a Hi Jacker plate and a 24 Raker prop. It redlines at 5500 with 61.8 speed tops with two adults in it! The problem that I am having is that it begins to porpoise at about 4000 to 5000 rpms. Any suggestions? I have recently raised the engine two more inches, but I haven't been able to try it out yet.
be afraid to let this combination rev to 6000 + rpm. Raising the
motor should help this. Hopefully when you try it out, this has
already happened. Vectors tend to porpoise a lot no matter what you
do. It is just part of the design of the hull. They run good
trimmed down going slow, or flat out trimmed up and not much in between.
Your speed will probably increase by raising the motor. If you have
excessive wheel torque, lower the motor until it goes away. This
would be your ultimate setup.
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