SS or Alumimum propellor

[rickr]

Recently I purchased a used SS prop. It's in good shape. I feel it's way heavier than alumimum prop I've been using.
Do you think it can increase top speed if I use it?
It could be another reason about weight because it's a 4 blade.

[JP]

Hi rickr. First off what hp age and make of boat and engine do you have? What was the pitch of the pro you had before the stainless on and what is the pitch of the stainless?
Stainless props have less flex under load and should improve hole shot. Top end speed does depend on boat design and engine make. Let me know what pitch and make and model and I can give you a better answer.
Cheers
JP

[rickr]

JP

My motor is Yr.93 115 HP Merc ELPTO. The original prop is 23 Pitch 4" hub. I can go 42 MPH under this one, but it was broken.
Late I used several alumimum props from 12.5*19 P to 23 P. The top speed is about 35~36 MPH (5000 RPM). Couldnt reach to 40 MPH.
The SS prop I purchased is 4 blade 13 * 23. It's much heavier than my previous props. I sort of worry my engine's load.

Thank you for help.

[mikemicropterus]

rickr You will probably not see any speed increase in fact you may go slower.
What is the redline of the motor????? I think it is 5400 or 5600, the 23 inch prop you have now is about 2 sizes to big. You should be running a 19 or 21 depending on load. Get you maximum RPM and then find a SS prop that gives you the same rpm.

Thats what I do I sell you a prop the fits your boat configuration not some of the shelf generic prop that MAY increase speed.

I can get you speed with the right rpm and just an aluminum prop with the right set-up but that is the problem with most dealers boats they are not set-up properly.

rickr to properly utilise a SS prop you need to get the boat at the right angle to the water and to acheive that you need a setback and to adjust the motor height and that is if the factory did not install the motor most dealerships don't install the motor at the right motor height. I would not put a SS prop on your boat until I installed a set-back. You just can't utilise the properties of the prop fully.

Here's some SS prop facts if you have a 19 inch aluminum an 18 inch SS will replace. 4 blades goes slower than 3 blades so if you want speed you want a 3 blade prop. If you have a 23 inch aluminum 3 blade and you replace it with a 23 inch 4 blade you will go slower it's just physics not opinions. When you hit rocks with a SS prop you get about 2 chances and then gears break.

I get my props and then have them worked to get the right rpm and that way you make sure you get the right prop and that's what you want if you are spending $500 to $600 for a prop. I rarely find one that does what you want right out of the box. Also it will need to be reworked every 3 to 4 years. My Gambler does 80 plus and last summer I put a few nicks in the prop so I lost a few mph, it will go in for a rework and I'll be back flying next spring. YEEEEEEEEEHAAAAAAAAAA