That's a 'piece of string' question!
You'll clearly need a coarser pitch prop than the one you're using, but the exact choice will depend on the load you're carrying and the use of the boat, along with such stuff as hull design, etc.
The 'standard' prop fitted to a Soozook 65 has a 15 inch pitch. Yours may not be standard - check by looking for the figures cast into the prop where one of the blades meets the hub. It will read along the lines of 12 x 15, where 12 is the diameter and 15 the pitch, both in inches.
I have a spare 16 inch prop, if you're interested.
I don't think it's 4" diameter! The 12" pitch should be 11 5/8" diameter, ie 11 5/8 x 12.
If the pitch is 12", then I'd say this will definitely be too fine, unless you're pulling a couple of waterskiers out with a few people on board.
I'll PM you on the one I've got.
with 120l fuel 2 adults 1 child and goods and saftey gear for a day out we read 30 knots on the gps on a calm day, (34 mph) at 5200 revs, the rev range is 5000 to 5600 at the top end so i think the prop is spot on, never had the chance to try it on my own yet but i would hope that on my own and with half a tank of fuel it would motor to 40mph on a calm day?!
Neb
just read your post and remembered that i have 2 dt 65 props in the roof.
I run twin 1993 dt65's and are now on stainless props so the alloy ones are surplus.
they are suzuki alloy 11 1/8 x 16 and would rev out on mine at about 5900rpm.
they are quite used but are sound and ding free...i sprayed them grey last time and the paint is peeling off.
