18SF planing speed and performance questions

[eggsuckindog]

Sorry to be so long but set up is not a single factor

You also should be able to check the pitch using a prop calculator - adding in speed and RPM and it should pop up with a pitch - conversely if add in pitch and RPM it will give speed, The Slip % it gives is the efficiency ratio 10 - 15% is decent, pretty helpful

I will also say that engine height makes a huge difference in planing, like if its too low - Mercs are a pain to change vs Rudes that have slots and you don't have to remove them. I will also say that the prop will have something to do with it also - the first prop I had I could not trim much at all until it started to blow out. I switched to the Stiletto and have raised it 2 holes and had it up 3 but brought it back down 1 - that prop never did blow out even 3 holes higher and the Cavatation Plate 3+ inches above the bottom. Currently its 2 1/2" but thats the prop 1 1/2" should be close with a decent prop, Stilettos are a bear to swing but offer great trim response.

Props do make an incredible difference one to another by the blade design and amount of cup - see my comments above

As mentioned above Prop Gods is an excellent help, Kens a stand up guy and is very helpful

A WOT RPM is the best indicator of where you are on prop size - each 2" in pitch will change the RPM almost exactly 400 RPM - then you can figure if you need more prop or less. You will have to get the motor height close before you mess with props but sounds like an up grade would make you happier.