3 blade vs. 4 bladed prop

[captian dave]

I have an 8 horsepower outboard. I understand that when it comes to powerboats, a three bladed prop moves a boat faster at WOT. My question is: given that i have a displacement hull sailboat and plaining is not an issue for me. Is there an advantage to have a 4 bladed prop? Will it give you more noticeable thrust when pushing through chop? will it noticeably affect gas mileage either positive or negative, if so how much? I assume that it will give more thrust at slow speeds and therefore more control at slow speed, or does it not make a big enough diffrence to bother? I would like to hear from someone who has experience with 4 blades vs. 3.

Thanks much,

Dave

 

[BobM]

Sounds like this might work for you. I was looking into them for my 8hp, but bought another boat. For the money, which is $90, it looks like it is an equivalent cost and claims to increase thrust and provide better fuel consumption. Can't beat that. Has anyone tried one? Other than that, a 4 bladed prop or a prop with a different pitch would likely provide more torque, which would likely be more helpful. However, it would also result in more drag. That isn't a problem if you have an articulating mount and can get the motor out of the water, but I always noticed a huge difference in boat speed when I lifted my motor up in light air.

http://shop.s2owners.com/detail.htm?fno=240&group=294

 

[sailingdog]

I've got one that I have to mount on my boat. I hope to have it mounted sometime this summer, but it is pretty low on the list of priorities.

The drag issue isn't one that worries me, since my outboard mounting system lifts it clear of the water completely when not in use.

Sounds like this might work for you. I was looking into them for my 8hp, but bought another boat. For the money, which is $90, it looks like it is an equivalent cost and claims to increase thrust and provide better fuel consumption. Can't beat that. Has anyone tried one? Other than that, a 4 bladed prop or a prop with a different pitch would likely provide more torque, which would likely be more helpful. However, it would also result in more drag. That isn't a problem if you have an articulating mount and can get the motor out of the water, but I always noticed a huge difference in boat speed when I lifted my motor up in light air.

http://shop.s2owners.com/detail.htm?fno=240&group=294