Stainless Prop Question

[Johnnielund]

I have a 1993 16'Lund Explorer powered by a 1990 Johnson 30 HP. MY prop is a 10 x 13 aluminum. This set-up yields 5800 RPM with just me in the boat. MY prop repair guy made the comment to me that I sould consider a 10 x 13 SST stainless prop. Said my boat would perform better. Is he correct or is he just trying to sell a prop?

 

[gator68]

Re: Stainless Prop Question

sell a prop!

 

[mollywalk]

Re: Stainless Prop Question

I have a 50 hp johnson and every time i ask about s.s. the response was it wouldn't make much of a difference on 50hp.<br />Well, I purchase an old use s.s. and it makes a little bit difference out of the hole but I only paid $35 for it. I had to sand it down and repaint it black.<br />Not the high qty s.s. as you can guess.

 

[gator68]

Re: Stainless Prop Question

been running aluminum for years. no problem

 

[walleyehed]

Re: Stainless Prop Question

Depends what your definition of performance gain is........The dealer, in this case, was actually telling you the truth. There would be a performance gain over std alum., in fact, you can bank on that anytime you replace an alum. prop with an ss prop with the same blade shape and design, it's just more efficient.<br />Now, if he were leading you to some other pitch or high rake design, I would say no, it's not going to help unless you optimize the set-up to begin with.

 

[Bass Man Bruce]

Re: Stainless Prop Question

Okay,I have a dumb question, how can the metal the prop is made of affect it's performance assuming both metals are strong enough not to flex under normal use?

 

[IBFishing]

Re: Stainless Prop Question

Originally posted by Bass Man Bruce:<br /> Okay,I have a dumb question, how can the metal the prop is made of affect it's performance assuming both metals are strong enough not to flex under normal use?

Aluminum will flex to a certain extent. Aluminum Props have thicker blades making them less effecient. Stainless Steel props are stronger and have thinner blades, which slices through the water easier, making them more effecient.

 

[walleyehed]

Re: Stainless Prop Question

Great explanation, IBfishing...<br />Also, a stainless usually offers a bit more cup, adding a bit more of an edge on the efficiency side..this also allows higher engine mounting heigth and trim angles, equating to better lift/speed by decreasing the wetted surface area of the boat.

 

[umblecumbuz]

Re: Stainless Prop Question

Listen to Kenny - he makes sense.<br /><br />On a Johnny 50 I took off a standard aluminum prop, 11.50 x 19, last week, and replaced it with a Stiletto 11.75 x 18. Not a huge difference in pitch, or big increase in diameter.<br /><br />I had already squeezed more performance from the alu prop by drilling and cupping it, but I felt I could get more.<br /><br />The Stiletto has transformed the boat! Because of its superior performance, I have now raised the motor which gives increased efficiency (stainless can often run higher than alu). As the motor is more out of the water, the boat is now proportionally heavier at the stern, so I have increased the pressure on my autotabs (not Smart Tabs, but TrimPilots, made here in Malta).This whips the stern up quicker and gives me flatter and faster holeshot.<br /><br />The final result is beyond my expectations. Holeshot is awesome and seems almost immediate, and I can run with the big boys. Wot comes up with no effort. I've lost a couple of mph at the top end, but I run in the sea all the time, and the limiting factor for top speed is often the state of the sea, so that loss doesn't bother me.<br /><br />All this started from just changing prop material.