Correct Prop? Need some help

[enginesilo]

Hi,
I am purchasing a 2005 Sea Ray 180 Sport bow rider type boat with the 3.0L Mercruiser engine. I was curious to know what a good replacement prop would be for this boat?

The current prop is a black aluminum type prop that isn't in horrible condition, but it has a few scrapes and I want to have a spare prop around.

What is a good pitch to replace the stock prop? What is a good pitch if I want to do some wake boarding or pull some type of water sport toy behind? I ride in the Long Island sound where it is salt, and can sometimes get rough so I definitely need something that can push through rough waters.

Any tips on the pitches to look for, and anything else that is required when shopping for a new prop will be helpful. Also, what the benefit and down sides of a specific pitch over another such as loss of speed, stronger towing, etc.

This is the boat:
http://www.searay.com/online_brochure.asp?display=brochure&tab=1&modelid=43694

 

[Dandelion]

Re: Correct Prop? Need some help

With that engine you want to be between 4400-4800 RPM's at Wide Open Throttle, preferably closer to 4800 without going over. If the engine is working as it should you're probably looking at either a 19" or 21" pitch prop to get you in range. A lower pitch translates into quicker acceleration from a stop (good for towing), higher RPM's at Wide Open Throttle, and a little less top speed. A higher pitch translates into slower acceleration, lower RPM's at Wide Open Throttle, and a higher top speed.

You could also try a 4 blade prop as opposed to a 3 blade prop. You want to drop 1" in pitch when switching from 3 blades to 4. In other words, if your 3 blade prop is a 21", get a 20" 4 blade prop for similar RPM's at Wide Open Throttle. The advantage to a 4 blade prop is enhanced low end performance, but at the expense of top end speed. I have a a 4 blade prop and love it.