I just acquired a 1985 Passport 40. It has been repowered with a Beta 50, topsat 2800 rpm
. I wouldn't know what the cruising rpm
should be. I do know that on the sea trial, we worked the engine
wide throttle, and the boat
wouldn't do more than 6knots. The engine
sounds great, but I really think it's underpropped. A 50 should push that boat
much better. But then again Im no expert. I requested a recomendation from MaxProp, and got back a completely different setup from what is currently on the boat. That kind of cemented my doubts, now I am almost convinced Im underpropped. But I could be wrong. What do you guys think?
Passport 40, 40ft, 23000 lbs displacement
Beta 50@2800 rpm, 2:1 transmission
, 1.25 shaft
Currently it has a 15x10 fixed 3 blade
Maxprop and the propcalc spreadsheet both gave me a 18x12 recommended prop
Anyone wants to shine some light into this prop dilema? To me it all sounds like black magic.