[LuciferUA]

Performance propellers are typically made of stainless steel, while the typical pleasure boat is equipped with an aluminum or composite propeller. Due in part to cost, the aluminum propeller blades are used because they can be easily replaced in the event of damage from striking an underwater object. Many times the aluminum propellers will bend instead of breaking. This allows an experienced repair person to reset the propeller pitch and straighten the bent propeller. In the case of a composite propeller, more often than not, the propeller blades will break off when encountering an obstacle.

[d1337r]

Propeller pitch determines the speed and power that a propeller will produce. The amount of propeller pitch refers to the angle of the propeller blades as compared to the propeller hub or a horizontal line drawn through the center of the propeller. By altering the propeller pitch or the angle of the blades, the propeller can be tuned to deliver more top speed or more slow speed power or torque. This is only part of the equation, however; propeller pitch is used hand in hand with propeller blade cupping as well as material used in its production to produce the proper propeller for any given application.

[virgo20]

Stainless steel propellers are much thinner than composite or aluminum types. This thin design coupled with the proper propeller pitch makes for a very high-performance propeller. Producing more speed at top end as well as being able to push the boat on plane much faster, the typical stainless steel propeller is engineered with the propeller pitch and cupping to extract the top level of performance from the outboard motor. This performance does not come cheap, and most stainless steel propellers are purchased at double the price of a comparable aluminum unit.

[flemingo]

The amount of cupping designed into a propeller has as much to do with its level of effectiveness or performance as the propeller pitch does. The cupping affects the manner in which the water spins off of the propeller blade. Much in the same manner as a baseball is controlled by the placement of the pitcher's fingers as it is thrown, the cupping controls the manner in which the water is actually driven off of the propeller blades. By increasing the speed at which water is propelled off of the propeller blades, the speed at which water can enter the area occupied by the propeller is also increased. A properly tuned propeller is actually pulling water from underneath the entire length of the boat's hull.

[Broggly]

here

[nx2059]

The 17 pitch prop turning 3700 rpm will move at the same speed as the 21 pitch prop at 3000 rpm.
If the 17 turns at 3800 rpm it will be even faster. [links]

[dammy09]

A clean, fresh 17P prop should get you squared away. more

[Pippin]

The engine will generally produce more power at 3800 rpm than at 3000 rpm.
More power means more speed.
Less could actually be more in this case. more

[sunglasses]

The 17 pitch prop turning 3700 rpm will move at the same speed as the 21 pitch prop at 3000 rpm.
If the 17 turns at 3800 rpm it will be even faster. more

[goodhope]

To turn the 21 pitch prop fast enough, you'd need about 200+ HP. more

[Hiro Protagonist]

Good day,
I just purchased a 2007 Rinker 226 Captiva bowrider. It has a 21 pitch aluminum propeller on it right now. My previous boat (17.5' Larson) had a "High 5" stainless steel so I'm worried about the aluminum prop on this one. Any suggestions or comments are welcome. I would like to purchase a stainless steel but what exactly should I go out and get? I mainly use the boat for skiing.

[Ddraig]

Before I can make a recommendation, we need to know details regarding your engine and sterndrive (ie. make, model, gear ratio, etc.).

[Jason]

I did hit something previously on my 1st prop, ski boating in new lakes and venturing to close to shore has it's dangers, it was aluminum and it sacrificed it's life for the better good. meaning it bent instead of my Alpha1 drive shaft. Stainless steel may look good, but unless your in salt water and want to corrosion resistance, I personally would stay with an aluminum prop. If I did have a SS and hit something, and my prop was still good. that energy was just absorbed by my leg and not my prop, I would rather pay $200 for a new prop vs big $$ for leg repair or replacement. I chose to run aluminum from that day forward and also carried a spare prop and prop wrench to make up for the downfalls of a soft prop. here

[BostX]

Better top speeds will be offered by a high pitch propeller but acceleration will be quite slow. Just keep one thing in mind that, by just fitting a high-pitch propeller to your boat along with a low horse power engine in any case does not refer that you will make your boat faster. more

[dmp1ce]

What kind of issues you are facing? [links]

[Regent]

The manual provided by the manufacturer will help you know about your boat engine specs and for which range it is made to speed-up.

[venom]

Let us start knowing them properly: