Originally Posted by HOBO-S34
I have a Sabre
34 with a Westerbeke
. My cruising speed at 2700 RPM
is max 5 knots. I can get a little more speed if I up the rev's to 3000 plus (only did that as a test). I think I am under proped. Any suggestion for a three bladed prop size. Boat is relatively new to me and I do not know the prop size.
The Hull Speed
on the boat is 7.12 knots with clean hull
and excellent conditions under sail
The engine produces max torque at 2,021 RPM - and 19 HP.
For best consumption/speed/sound - around 1,800 RPM.
Max rated RPM on that engine is 3500 = 27 Hp
Your cruising speed is 5 knots at 2,700 RPM (+/- 22HP)
a new prop with different diameter or pitch
Dive and check the prop and hull
for fouling. It they are clean, measure the diameter - can't measure pitch
easily under water
The Sabre 34 may have a user group who can advise on the size/pitch they have found best suits the engine and the gearbox's reduction ratio