I believe you are on the right track.
Rather than discuss the specifics on this forum, email me at [email protected] and I will do my best to help you.

Brett

Hello;


We have next results:


originally propeller:

3.500 rpm = 22,5 mph = 3,17 gph
3.800 rpm = 25 mph = 3,7 gph
4.000 rpm = 27 mph = 4,2 gph
4.500 rpm = 31 mph = 5,8 gph
5.300 rpm = 36 mph wot


cutted on 13, 65", but with out of cup along rake lines:

3.800 rpm = 19 mph = 3,17 gph
4.000 rpm = 21,4 mph = 3,96 gph
4.500 rpm = 25 mph = 5,28 gph
5.400 rpm = 31,5 mph wot


same cut, but 0,12" cup along rake lines:

3.800 rpm = 2,5 mph = 4,23 gph
4.000 rpm = 24 mph = 4,5 gph
4.500 rpm = 27 mph = 6,6 gph
5.100 rpm = 31 mph wot

Any comment?
I do not understand:
- originaly prop have diameter 14 1/4" and when we cut it down on 13, 65 we reach only 100 rpm on wot. In this phase I am cut cup and we did not made new cup. In third thest I am make ca 0,12" deep cup along rake lines and motor achive les rpm on wot like at originally 14 1/4" diameter.

Any other reasons like engine, plants on hull bottom...? Boat it is one month in Mediteran and have no anty fouling.

If I go on Suzuki web page I find that boats with same weight go much faster and same engine achive with originally 14 1/4x22 prop almost 6.000 rpm, we are far away from this rpm.
Engine it is arrive new originally from Italy in 2011 together with boat and work just fine, only this wot number make us confusion.

that is not the right prop for your boat you need to try a lower pitch in 14 1/4" diameter, try a 20" prop

Yes, agree, but with 14 1/4 x 22 prop!
This boat is from one my friend and not mine. Today he find, that engine have wot limiter at 5.500 and not 6.000 rpm like he told me before. Now I have clear all case.
I am sure that Suzuki have soft limter and it mean slowly slow down round 5.300 rpm...

never heard of this maybe they start to make an alarm before 5600 but shouldn't stop until 5600 if that is the limiter.

Lot's of engines today have soft limiters before they shut you down completely.

It is hard to comment on your prop work since we are not seeing it's transformation. Diameter, blade area and cup work are quite specialized and can make large differences in performance when done exactingly.

Brett

Hello;


Friend is clean vegetation from hull and now he has excelent results. Better hole shot, less fuel consumtpion at travel and 2 mph higher end speed.
:thankyouthankyou:

Awesome!