1986 aquasport 170 with 115 evinrude 1993 13 x17

[Jchevy1990]

I have 1986 aqua sport 170 1986 with 115 evinrude top speed
38mph does this sound right prop is power tech 17p shows rpm is 5000

[RickK]

That's about normal in my experience - bridging the 40mph mark is the challenge. Check the specs to see what the top RPM should be and then you change the prop pitch to get to top rpm.

[boatnamesue]

I believe the WOT rpm range for your motor is 4500-5500.  But given you're nearly at top end range with 17 prop pitch, dropping pitch just to gain 500 rpms doesn't sound worth the effort.  Unlikely you'd see an increase in speed with this extra 500 rpms, if that's what you were hoping for.