Good day everyone,
Looking for some help in re-proping my trimaran
. I have a 38' trimaran
, spec displacement
is around 9000lbs I do not know the actual displacement/weight. Currently I have a Universal M25 powering it with a 15x13 3 blade
prop. In this configuration I get a maximum RPM
of about 2100-2200 out of the boat at which point I get a good amount of black smoke as well so I usually back it off and cruise
around 1900-2000 which gives me about 5.5 knotts on a good day. However, this engine
should max out at 3000 with a cruise
around 2600-2800. So, it is obvious that I am over proped.
I have read and run around some calculators and have come up with a "recommendation" of a 3 blade
15x10 prop. However, I was also wondering if a 14x12 prop would also work and if there would be any difference between the two? My goal here would be to raise the operating RPM
of the engine
to more within specs to utilize all of the power as well as to hopefully gain 1-2 knotts of cruising speed so I am not entirely sure which blade would be more effective and efficent at doing that.