Is this sound right

[R1racer]

Got an 1998 Evinrude 200hp on a 238 WA Neptune sunbird that hanging of a platform, RPM @ WOT 4900 with top speed 42MPH GPS reading, I know Eng should be 5500RPM at WOT, My Michigan prop rapture SS size which came with the boat 14.25x19, SO i called one of the local dealers around they said am running high pitch 19.

They told me to take it down to 14.25x17 to achieve my WOT 5500 peak performance. Which could be done by taking the prop to local prop shop and get them to re-pitch it as it?s cheaper than buying a new SS PROP...???

Am not looking for a speed on a such boat am looking for the best performance out of this board..SO is this sound right
.

 

[Bifflefan]

Re: Is this sound right

2"p on a prop is about 400 RPM at the same MPH.
I dont know about repitching a SS prop. Used SS props are real cheap. At least around here, no one wants them.
Take yours to a prop shop and see what they say, most will take it on trade for a new or used one.

 

[Dhadley]

Re: Is this sound right

You're at about 12% slip right now. If a prop shop reworks your prop simply to gain rpm the will take away efficiency. 4900 is pretty hard on your motor, you are right in thinking you need to get the top rpm up some. We normally look for 5800-6000 with that motor. If you're using ethanol fuel you may not get that much.

If it were mine I'd start with set up - assuming the motor is running right. I'd look into raising the motor before spending $$. If the prop is in good shape and you can go up that will increase the overall efficiency. If you just want to go to a 17 shoot me a PM, I know where a really good 17 is.

 

[R1racer]

Re: Is this sound right

2"p on a prop is about 400 RPM at the same MPH.
I dont know about repitching a SS prop. Used SS props are real cheap. At least around here, no one wants them.
Take yours to a prop shop and see what they say, most will take it on trade for a new or used one.

So pretty much with 14.25x17 or at the most 15x17 sound pretty much right for this Eng ..? I don?t have much experience with prop set up or pitch effect to RPM ratio, I kind looked in the book to understand it some what

 

[R1racer]

Re: Is this sound right

You're at about 12% slip right now. If a prop shop reworks your prop simply to gain rpm the will take away efficiency. 4900 is pretty hard on your motor, you are right in thinking you need to get the top rpm up some. We normally look for 5800-6000 with that motor. If you're using ethanol fuel you may not get that much.

If it were mine I'd start with set up - assuming the motor is running right. I'd look into raising the motor before spending $$. If the prop is in good shape and you can go up that will increase the overall efficiency. If you just want to go to a 17 shoot me a PM, I know where a really good 17 is.

12% slip ..Not sure what that mean as am all new to this prop set up, The motor set up is correct as it?s all factory set up and nothing changed, New throttle/shift cable about a moth go and adjusted by the dealer ( unless they didn't do it right) ... I run fuel with no Ethanol and if there is any i treat it to the best I can ...I had 130hp prior to this one used it around the same water way ran perfect on the same fuel I buy now

 

[Dhadley]

Re: Is this sound right

Please don't assume the "factory" set up is as good as it gets. In most cases it's far from that....