"Agressivelness"" of Yamaha painted SS props

[smitty477]

I have read enough on this site to learn that all props of the same pitch are not equivalent.
Some posts indicate that certain brands and types can be more or less agressive and behave like a higher or lower pitch.

I currently have stock Yamaha painted SS props on my 150 four strokes.
When considering the change to 4 blade props how do the Yamaha painted SS compare?

When comparing them to 4 blade products from TP, Turbo, & Solas do they generally lose about 100rpm's off of a 6,000 rpm base from the Yamaha painted SS?

Thank you

 

[steelespike]

Re: "Agressivelness"" of Yamaha painted SS props

Even the experts can't take this one. I think that prop technical info is so vague, bow lift ,stern lift , rake ,cup better hole shot
better top speed,better handling, better mileage better cruising speed, aggressive. You notice no numbers are mentioned by me, I think if you do research you'll find the same type of rhetoric. If your going to go from a 3 to 4 blade Yamaha painted ss prop It would be normally suggested to drop one inch in pitch to maintain rpm. Whether your setup would do that would depend on your present wot rpm and speed and your satisfaction with your setup.

 

[Philster]

Re: "Agressivelness"" of Yamaha painted SS props

Yep... generally, the more aggressive props are cut from SS. Generally. There are 'vanilla' SS props, too, with key words such as 'value' prop, or 'all purpose'.

But, there are some pretty aggressive alum props, too. Merc makes one called the Spitfire, as an example.

 

[smitty477]

Re: "Agressivelness"" of Yamaha painted SS props

Steelspike & Philster -

Thank you for your replies - from searching on this topic I was not really getting any data to work with and you certainly have confirmed why that is.
I did eventually find a perf bulletin on the painted SS prop on a skeeter that calced to a slip of almost 0% so I guess they are pretty high on the pitch design.
In a recent test I just ran the boat at 6,000 and 51 mph with full fuel , 3 adults on board, 97 degrees & high humidity but iut did not seem like it had much left. The boat does prefer higher engine mounts and more trim giving more rpm and speed but I become limited by blowout.
I tend to believe that the 4 blades with stern lift will add to trim and height so the pitch decsion is a bit hard to figure.
Thanks for your help

 

[smitty477]

Re: "Agressivelness"" of Yamaha painted SS props

After some additional research it appears that my painted SS 19" props were not intended for the 150's as far as I can tell.
Apparently Yamaha produces a couple of versions of these painted SS 19" props.
The ones I have are 14.5" X 19" and that larger daimeter is normally intended for the larger 4 strokes.

Can anyone venture a guess as to what that might mean when I shop now for a 4 blader with less diameter?

Thank you

 

[smitty477]

Re: "Agressivelness"" of Yamaha painted SS props

spLooking to get any feedback on my guess here before I go and buy a pair of props.
Moving from the 'too large' painted SS Yamaha props of 14.5 X 19" (intended for 200 hp and up) which turn 6,000 rpm now.
My best guess is to try the Solas HR Titan 4 blade as the next move so here is some of my 'guesstimate' math open for debate....

-75 rpm loss going to a 4 blade prop in the 19 & 20 inch sizes
+150 rpm gain going to a 1/2" smaller diameter
-150 rpm loss going to a 20" pitch
+75 rpm gain from the lift and grip allowing a higher engine height and trim out

So my guess is that a 14" X 20" Titan Solas 4 blade will turn about the same rpm's as the 14.5" X 19 Painted SS Yamaha props.

What do you think of this guess? (and thanks for the help)

 

[scca vette]

Re: "Agressivelness"" of Yamaha painted SS props

The painted stainless is just a "general" prop and they are offered for about any HP. If you want the most out of your 150 I think you need to look at our Reliance series. The pro series might also be a good option for your boat.