What affect does being over propped have on top end speed?
I ask because I am only getting 35mph (4200rpms) with my setup.
My setup is setup is: 18' flats boat with a 1990 115hp Mariner. The prop is a Laser II 20p SS. I've calculated the boat/motor/gas and me should weigh between 1800 and 2000lb.
I realize changing to a 17" prop will get me higher rpms, but will it have much affect on top end speed?
Based on speed calculators on the internet, my boat has the potential of high 40s.
Is an oversized prop stealing 10+ mph from me?
Also, the boat is currently in line for a tune up. I'm guessing there maybe a problem with it.
Thanks
Steve
I ask because I am only getting 35mph (4200rpms) with my setup.
My setup is setup is: 18' flats boat with a 1990 115hp Mariner. The prop is a Laser II 20p SS. I've calculated the boat/motor/gas and me should weigh between 1800 and 2000lb.
I realize changing to a 17" prop will get me higher rpms, but will it have much affect on top end speed?
Based on speed calculators on the internet, my boat has the potential of high 40s.
Is an oversized prop stealing 10+ mph from me?
Also, the boat is currently in line for a tune up. I'm guessing there maybe a problem with it.
Thanks
Steve