I am getting about 5100-5200 RPMS at WOT trimmed up with a 19 pitch prop on my 18ft deep v. I am getting plenty of speed is there any reason to reprop for 300 RPMS?
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I am getting about 5100-5200 RPMS at WOT trimmed up with a 19 pitch prop on my 18ft deep v. I am getting plenty of speed is there any reason to reprop for 300 RPMS?
those 115's love RPM, if you can find another prop cheap, then go for it, if not I guess put up with it, has your setup been checked for best performance like as in engine height and so on?
Your motor doesn't put out 115hp until 5500 rpm and the max operating rpm is 5800. If you prop your rig in the middle of that range (5650) or so, the motor will perform at its peak.
yep, that is what I was saying (well tried to say) they love RPM to be right up there, anything much less and you are doing your motor no good at all.
My question is by running the motor at these rpms will it hurt anything? I am happy with the speed and have no want to go any faster, so I am having a tough time justifying another 400$ for a prop??
So if I am happy with the speed is there any harm I can do by running it here?
you are right on the limit for being over propped, and long term, you will do harm, and sometimes major harm, you will still get the same speed with a smaller prop, because your motor will be able to rev further (as it was designed to do) you fuel economy will be the same, simply because your motor is "breathing easier" at the moment you are using your motor like your car would be if stuck in over drive, it is labouring all the time and eventually you will kill it bfore it's time is really up.