Composite Piranha Prop

[bryancx94]

Boat: 17' starcraft 1700, 94 mariner 90HP 3cyc, 2cycle.

How do these props compare to a Hustler ALUMINUM Prop. I am torn between the two. My current prop is 14x19 ALUMINUM. I am currently over proped at 4900RPM WOT, I should be at max 5500RPM. I am thinking of dropping down to a 13 1/4 x 17.

I boat in a river where the levels are sometimes shallow and I knick my prop up. Since the pirannha's have removable blades, I thought this maybe a better choice. However i need to be able to get on plane quicker than now, and have a better holeshot for skiing, top end is important, but not a major concern, I just don't want too lose any top end Thoughts? Thanks!

 

[walleyehed]

Re: Composite Piranha Prop

Well, everyone wants hole-shot but doesn't want to lose any top-end.....
So far, the only way I've found to solve this problem is to over-power considerably. (Don't try this at home!!!)
Finding the sweet-spot is the secret, and that "may" involve lifting the engine on the transom...maybe adding some set-back, and experimenting with many props.
If your engine says 5500 is where it should be, then the 17P "may not" get you to that point, but it will help.
The composite props tend to flex under a load, and due to this, it increases the effective hole-shot(Faster).
The problem I've run into with composites is, you better keep a couple of sets of blades around. If you hit anything, it "usually" shells the whole blade....not just a small nick.
I would go with aluminum just because it's a bit tougher, but the choice is yours.

 

[maxxpower]

Re: Composite Piranha Prop

I replaced my stock aluminium prop with the same sized piranha 2 years ago. I boat in a relatively shallow lake and ended up nicking up my stock prop. I have not hit anything in the last 2 boating seasons so I do not know how easily the blades break, however I have touched bottom a few times with no damage. I would rather replace a $15 blade than run an out of balance prop and risk damage to my lower unit. As far as performance, a little better holeshot and about 1mph top end loss

 

[hal2814]

Re: Composite Piranha Prop

I bought Pihrana's closest competition: the ProPulse. It's a composite with adjustable hub so you can repitch it without changing the blades. I found it on sale at West Marine so I picked it up to play around with. It's now my primary prop. If you hit anything wooden or rocky you will certainly destroy a blade. I've never lost a comp blade to the mud. Stupid low lake levels. The replacement ProPulse blades are $20 but you don't have to go hunting specific pitches since the pitch is adjustable just by twisting the hub so I can generally find one in stock. I did lose 3-4 mph but that's moving from a 3-blade stainless to a 4-blade composite.

 

[bryancx94]

Re: Composite Piranha Prop

Hal that sounds like a cool idea for a prop, esp if you are wanting to test different pitches. You say you lost 3-4mph, but I would assume you could gain that back if you raise the pitch up, but then you would sacrafice low end I would assume. My biggest problem now is with pulling skiiers, the boat drags to get on plane, thats why I am wanting to go from a 19 to a 17. Do they offer a 3 blade model?

 

[hal2814]

Re: Composite Piranha Prop

No 3 blade for the Propulse. According to the website they only use 4 blade for due to balancing issues. And I can gain that 3-4mph easily at the expense of hole shot. I rarely have the need to go past about 35mph so I haven't played around with pitch much. You can check out their website at propulse.se