Can a specialty prop add speed?

[JasonLepore]

My toon was hitting around 40 now it's about 36-37...

I know I have a knick or 2 from debris.. Is there any specialty props out there that add speed?

 

[Bamaman]

Sure. You might find a specialty prop that adds speed, but there will always be a compromise. Chances are that it might not accelerate well.

The whole trick is to find a prop that does what you ask of it--and has sufficient speed. The boating world has decided that a prop with 1/2 a load and 1/2 tank of fuel that just pulls the engine redline is the best general use prop to have.

But, if you're pulling water skiers or big tubes, you might do better with a prop with 2" less of pitch. If you were going on a long river cruise and you were after optimum fuel mileage, you might have a prop with another 2" or 4" of pitch. It's just like changing gear ratios on a car/truck.

As cheap as aluminum props are, it's just not that expensive to have a couple of different props for different uses--depending on what you're going to be doing that day. And then you've always got a spare propeller on board.

 

[cwag911]

My toon was hitting around 40 now it's about 36-37...

I know I have a knick or 2 from debris.. Is there any specialty props out there that add speed?

It would help if we knew what you have for a boat and motor.

 

[JasonLepore]

2254 sti tritoon with Yamaha 150hp..strakes on center full length tube.. I have to check what size I have on their.. I forgot the size of prop

 

[Ben & Suzy]

The answer is a definitive YES! It takes lots of testing to overcome compromise.

 

[Bamaman]

HEY BEN! WHAT'A PROP! THE 150 HP SUZUKI IS PUSHING A 2.5:1 GEAR RATIO--NOTHING LIKE ANY OTHER 150 HP ON THE MARKET. THEIR PROPS MOVE SLOW BUT ARE THE LARGEST IN DIAMETER--THUS HAVE TO HAVE A LOT OF PITCH.

WHAT PITCH PROP ARE YOU PUSHING?

 

[StevL]

My toon was hitting around 40 now it's about 36-37...

I know I have a knick or 2 from debris.. Is there any specialty props out there that add speed?

More than likely if you clean your logs you will see that 40 again. You can also play with props.

Steve

 

[Ben & Suzy]

HEY BEN! WHAT'A PROP! THE 150 HP SUZUKI IS PUSHING A 2.5:1 GEAR RATIO--NOTHING LIKE ANY OTHER 150 HP ON THE MARKET. THEIR PROPS MOVE SLOW BUT ARE THE LARGEST IN DIAMETER--THUS HAVE TO HAVE A LOT OF PITCH.

WHAT PITCH PROP ARE YOU PUSHING?

I try lots of props. As you can see on the back of the boat, I have numerous hub kits. This is the first motor that I've owned where theoretical speed vs actual speed isn't anywhere in the ballpark. It's crazy. It runs much faster than the theoretical 100%, which isn't possible, again in theory. This motor is supposed to have a final gear ratio of 2.5:1 , but the GPS numbers tell me it's much taller geared. Maybe it has something to do with the ratio of the gear reduction unit between the powerhead and the actual gearcase ratio. Either way, it don't add up.

It accelerates hard and has great top end for a 150. What pitch depends upon the design of the prop.

Keeping the tubes clean is a must if you want consistent speeds. Our boat is a 2004 and the tubes are always clean.

 

[Bamaman]

I try lots of props. As you can see on the back of the boat, I have numerous hub kits. This is the first motor that I've owned where theoretical speed vs actual speed isn't anywhere in the ballpark. It's crazy. It runs much faster than the theoretical 100%, which isn't possible, again in theory. This motor is supposed to have a final gear ratio of 2.5:1 , but the GPS numbers tell me it's much taller geared. Maybe it has something to do with the ratio of the gear reduction unit between the powerhead and the actual gearcase ratio. Either way, it don't add up.

It accelerates hard and has great top end for a 150. What pitch depends upon the design of the prop.

Keeping the tubes clean is a must if you want consistent speeds. Our boat is a 2004 and the tubes are always clean.

IF YOU'RE GETTING SPEEDS HIGHER THAN ANTICIPATED, IT PROBABLY MEANS YOU'RE GETTING LESS SLIPPAGE THAN EXPECTED. I DON'T BELIEVE THERE'S ANY GEAR REDUCTION, AS THE POWER GOING INTO THE LOWER UNIT IS 1:1--THE GEARS ARE IN THE LOWER UNIT. THAT'S GREAT THAT YOUR BOAT PERFORMS VERY WELL. I WAS LOOKING AT THE SUZUKI PROPS, AND THEY USUALLY RUN FROM 17 TO 27 AND ARE VERY LARGE IN DIAMETER. OTHER BRANDS OF PROPS ARE MORE LIKE 11-23 PITCH. I WAS THINKING A SUZUKI 150 POWERED TRITOON WOULD BE RUNNING MORE LIKE 19 TO 21 PITCH, AND DIDN'T EXPECT TO SEE A 4 BLADE PROP BEING USED. IT LOOKS LIKE THE SUZUKI IS A GREAT PICK FOR A MID-SIZE, MID HORSEPOWER PONTOON/TRITOON.

 

[Ben & Suzy]

Suzuki does use a gear reduction unit under the power head. It is not just a straight driveshaft at 1:1 going into the gearcase. 2.5:1 gears will not fit into the case therefore it requires a reduction box.

What I meant by 100% is the efficiency factor, meaning 0% slip, which isn't possible. Therefore there are only a few variables........primarily rpm, pitch, or gear ratio. The tach is on

the money and since I have access to a pitch gauge, I know the pitch. It comes down to gear ratio IMO.

At any rate, it runs exceptionally hard for a 150. Maybe there's something extra special under the cowl?$?

 

[mtudb24]

We're the same way. We are faster then the theoretical speed calculator. Not sure why or how. I even tried it at the 165hp that the optimax pro xs is allowed to have under law, but no dice........?????

 

[Ben & Suzy]

I'm not aware of any speed calculation that uses hp as a factor. I think you just love knowing that your motor meets / exceeds that +10% rule and can't help yourself with the 165hp thing.......it just comes out!

I think the Enertia may be an excellent choice for his boat also. I'd love to try one myself just to compare, but the Enertia drops diameter as the pitch goes up and my Suzuki requires much more pitch and diameter.

 

[mtudb24]

If you want to borrow a Enertia prop let me know. I have both a 14 and 15 pitch plus a vengeance at 13 which is too small for me