3 blade or 4

SpinnerBait_Nut

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What difference does the number of blades make on a prop?<br />Is 3 better than 4 or what?<br /><br />Cupped or not cupped?
 

JB

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Re: 3 blade or 4

The amount of blade surface on a prop will determine its drag, SBN, and bite, too.<br /><br />All other things being equal, the 4 blades will give you a better hole shot and lower your top speed.
 

SpinnerBait_Nut

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Re: 3 blade or 4

ok, cool. So my 24P 3 blade LaserII would be better on topend than a 4 blade would then?
 

Dhadley

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Re: 3 blade or 4

Todays 4 blade props are often faster than the same design 3 blade props. They dont run at the same X deminsion. If youre talking about the same design style, the 4 will run higher. If you run a 4 blade at the 3 blade height you may lose some top end.<br /><br />Now, if you start talking about the large diameter 4 blades, like a 4 blade Lightning, you can run even higher. And get more lift, speed, holeshot, economy etc. Usually a good 4 blade will carry the boat better even in mid range.<br /><br />What kind of boat do you have? Does it have a jackplate?
 

SpinnerBait_Nut

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Re: 3 blade or 4

Thanks Dhadley, it's an 18' Ebbtide Bassboat.<br />I am running a Quicksilver 13.75X24 LaserII on it now.<br />I am turning right at 6000 RPM's on a 150 Mariner MagII.<br />It is on a jack plate.<br /><br />The little trim tab on my lower unit will not fit because this prop hits it.<br />Does this tab help in the torque of the engine?<br /><br />Mine torques real hard to the right.<br /><br />Again, thanks.
 

Dhadley

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Re: 3 blade or 4

Thats common to remove the tab. Yes it is there to help offset the prop torque. But its also common that when running combos like yours that the tab is high enough that its out of the water. So even if it was there it may not do much.<br /><br />Not to worry. There is a solution. Get a skeg mounted Torque Tamer. It attaches to the skeg and takes the place of the tab. Check them out at www.bobsmachine.com for pics and youll see its pretty simple. They probably sell them here at iboats too.<br /><br />Pretty nice ride. It should be fun. Were you thinking about a 4 blade?
 

SpinnerBait_Nut

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Re: 3 blade or 4

No, was just wondering what the difference was and what I could change to compensate for the torque.<br />Would the skeg having a little bend in it have something to do with the torque also?<br /><br />I noticed mine has a little bend in it, not bad, but you notice it.<br /><br />EDIT: This is it.<br />
boat18co.jpg
 

Dhadley

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Re: 3 blade or 4

A bend might have a very small influence on it. That Torque Tamer will correct the problem youre having. Very common, no big deal. On the race boats we create our own by welding on the skeg and the use a grinder to shape it and "dial it in". The little attachable ones will do everything you need it to do.
 

SpinnerBait_Nut

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Re: 3 blade or 4

Thanks OBJ, I went and looked at them.<br />I just plan on this boat one more season and then plan on getting a newer one so I don't think I will drill any holes in it anywhere.
 

walleyehed

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Re: 3 blade or 4

Otta see what happens when a customer install a torque tamer on the wrong side of the skeg!!!!! :D Had a guy in Texas last year got'er done that way! Said it was all he could do to hang on to the wheel as soon as the boat planed out. Needless to say, we switched'r over for him.......Texans...ya gotta love'em! :D
 
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