Massimo,
Your question could have a very long answer...prop sizing is not an exact science.. You need to know your gearbox ratio and check the shaft diameter and taper are correct. Also know your max RPM and HP of your engine. Use the waterline length, beam and displacement and google "prop size calculator". It sounds like the prop may be suitable but these calculations will help you.

John Maramu #91

Hello Members....
We are glad to be part of your club.. thanks!!!
Wereally need help, We bought an euros 39 a couple of years ago..
The
boat "Calypso" is in very good condition, but unfortunately is very
slow... she has the main sail rolled in the mast and i think that the mast is
been reduce either .
We
are leave liveaboard, we sail always, (diesel is expensive) we really need to
scrap another 1/2 kts to the boat speed and we also plan to cross the atlantic ...
I
like to change the propeller with one foldable and I found one second hand 18 x 16
volvo 3 blade
I
look around in other forum for information, the only one helpful was a guy with
an euros 41 which he mont a prop 19 x 15 on his boat with a janmar engine and
he is quite happy.
Calypso
has the original volvopenta MD21B with the borg warner gearbox...can some
member please tell us if we can put this volvo 18x16 or if is not suitable for
us?
Any
suggestion act to find a proper used foldable prop will be very appreciated...
Many
thanks
Massimo
e Deseley Bocchini

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