4 blade?? Maybe some rake??

[studlymandingo]

I have an 18'6" center console with a 150 V-6 Mariner mounted on a jack plate with 10" of setback. I am currently running a 14.25 X 21P vented Rapture SS prop that propels the boat to about 48 (GPS) at 5400 RPM.

When I have a load, the boat wants to porpoise more than I would like. The boat rides nicely out of the water with the jack and setback, I feel that I could use some more bow lift and I am wondering if an additional blade or perhaps a prop with more rake is what I need.​

 

[Tail_Gunner]

Re: 4 blade?? Maybe some rake??

Walleyehed has rarely recomended 4 blade's for outboard's, doesnt seem to like your prop either if i remeber right. Id give him or Dhadly a pm for best result's, those two have a lot to share, In I/0's we cant play lie you O/B guy's can so we settle for the finer point's , you know smoothness, lift and econ and just maybe a speed bump.....

 

[studlymandingo]

Re: 4 blade?? Maybe some rake??

Yep TG I know what you mean about the I/Os; the first 3 boats I bought and restored were Mercruisers, and there certainly wasn't a lot that could be done for setup.

BTW: my boat has Smart Tabs, when I increase the tension on the actuators, it stuffs the bow too much and decreases my speed.​

 

[Esox]

Re: 4 blade?? Maybe some rake??

Yeah. Not sure I would go 4 blade. Last year when I first posted on my setup Kenny and some other said stick with a 3 blade. Some of the props he recommended for my rig (heavy 18' deep v aluminum) were the Merc Enertia, Turbo 1, Raker and Turbo Lightning. At the time I was running a MWC ballistic and wasn't happy with it - has venting problems. After buying a Turbo 1 and not getting the results I wanted I am now leaning towards the Turbo Lightning. I also have a jack plate like you but I only have 5" of setback. Seems like Kenny and Dale don't frequent the prop forum too often anymore. Like TG said you may want to shoot one of them a PM. Not sure if you've seen these threads before but it may be of some help.​

http://forums.iboats.com/showthread.php?t=178446​

http://forums.iboats.com/showthread.php?t=162500​

 

[rndn]

Re: 4 blade?? Maybe some rake??

I would strongly suggest a four blade SS prop. I know some people don't like them but I have had nothing but the best of luck with them and would never go back to a three blade design.

 

[walleyehed]

Re: 4 blade?? Maybe some rake??

rndn, your rig, with a Turbo1 will out-perform anything you can run on it...I've done it. Now, as for me not liking 4-blds, thats not completely true...there is a time and place...if it's on an outboard, you really need to have it on a jackplate or you're waisting technology because you can't use it...Yes, I've tried.
On the Crestliner, A Turbo1 3-bld with eng in third hole will smoke a 4-bld with no jackplate.
We are begining to see some of the new Turbo designs showing some excellent numbers on some of these rigs. Total balance and hull design, along with available power seem to be the main points of variation that are affecting these designs.
Studly, I did get around to finally sending you a PM.

 

[studlymandingo]

Re: 4 blade?? Maybe some rake??

Kenny and everyone, thanks for the help. I was really concerned about throwing around a bunch of cash with no real direction.​

 

[Tail_Gunner]

Re: 4 blade?? Maybe some rake??

rndn, your rig, with a Turbo1 will out-perform anything you can run on it...I've done it. Now, as for me not liking 4-blds, thats not completely true...there is a time and place...if it's on an outboard, you really need to have it on a jackplate or you're waisting technology because you can't use it...Yes, I've tried.
On the Crestliner, A Turbo1 3-bld with eng in third hole will smoke a 4-bld with no jackplate.
We are begining to see some of the new Turbo designs showing some excellent numbers on some of these rigs. Total balance and hull design, along with available power seem to be the main points of variation that are affecting these designs.
Studly, I did get around to finally sending you a PM.

Ohh hello there Mr. stuck up.....

 

[walleyehed]

Re: 4 blade?? Maybe some rake??

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