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motor mounted low

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Lower the better IMO.

But you've gotta strike a good compremise between a productive prop length, and a good safe propeller tip clearance to all adjacent items on the boat.

So it all depends on what prop lenght is gonna be best for your power option, and how your boat transom, and engine stand are configured.

I guess theres no correct answer for your specific question, just opinions such as I've offered.

I have read an very interesting theory posted by Waterthunder, and how the engine stand hieght will effect the boats performance, under different circumstances. If you search his past posts, you may be able to dredge it up. It's worth reading.
 
There is a direct correlation between downward force on the bow and engine height. Also when the motor is higher the boat will torque roll more. Due to higher horsepower levels car motor gearbox boats are the most sensitive to engine height. Two or three inches will make a very noticeable difference. With the carbon fiber props on a ride boat I keep the tip’s 1 ½ inch off the bottom on race stuff I try for 3/8 of an inch. Of coarse the lighter and smaller a boat is the more noticeable these changes are. So if your running a 16ft tour boat this height will not matter as much as a 13ft ride boat.
 
That boat will do exactly what you want it for. Something that is 20ft long you will not notice a few inches of engine height. You would have to go to a lowered drive to notice any changes. You MUST be very specific on what you want your boat to do when deciding between a lowered drive or a standard drive!
 
Thunder that 1.5 inches would be from the deck on a deckover correct?? in a open hull situation I like to have maybe 3" of prop inside the transom some like more some like less I dont want my prop to pick up anything from the bottom of my boat. I feel if it is there it shouldn't get sent through the prop even if its water.
 
I posted some pics of the boat in the gallery and it looks like the motor is ialmost on the hull?
 
Fowbish, welcome aboard.

I am not trying to sound like a jerk so please don't take this the wrong way...there is a lot of information archived in old posts on this site. If you use the search tool located in the blue wording to the upper right of this screen you'll access answers to almost any question you may have.

People will be more than happy to answer a direct question but sometimes the same questions are answered over and over each month.

Talk to basketcase, he has a lowered belt drive I think.

Adam
 
I see what you guys are saying about the 3' to 5' inside the open hull to keep from drawing things into the prop. But we learned early on that a empty ( pop) can will still be drawn into the prop even with it 3' below the transom.... I done an air flow test on our boat -- boy that was education that was--- Then I had two different aviation design engineers watch the video --- They both told me the same thing This causes excessive noise and a reduction in performance. Two of the things that we all are trying to improve on. So my next hull will have a new design of mine to see if it helps with both sound and performance.
 
SCOUT, sorry to be a problem! All I was trying to do was trying to get some help as far as this boat that I am willing to pay too much for but to atleast have one! If you don't mind I will look up a " lowered belt drive" if you tell me how to get the answer. I tried it and I guess that I am stupid enough to not know what I am trying to search for. THANKS FOR ALL THE HELP
 
fowbish,
I don't think BPS was trying to say people don't want to help.
I think he was trying to say they might not give you the whole nine yards, cause they may have written lengthy posts regarding a topic on several preveous occasions. You may get better info faster by searching the forum.

He's right about that long belt drive unit, and Basketcase302 is the only one I know off that has one.

You should contact him via personal messaging for better feedback on that set-up. Or just wait, and he'll jump in here sooner or later.
 
Ron, you're right about hiding too much prop. When the prop tips pass the transom they reflect the shock waves and thrust coming off of them right back off the transom itself. That not only wastes thrust, but it captures a lot of sound that would have been dissipated otherwise.

I'll be interested to see your design.

BF
 
Hey FOWBISH, CALM DOWN!! I am trying to help you!!! Remember, we are all reading these words off of computer screens so you don't get to hear or see the way I say things. I tried to make that posts as non-confrontational as possible.

Cowboy hit the nail on the head. There is tons of info on this site and frankly people get tired of repeating it constantly. I never said you were stupid and never will accuse anyone of that simply base off an internet conversation. I hope you find your answer....

Adam
 
Hay fowbosf I too did not mean to pass you by the 3' prop below the hull was after you first post but
As far as the low drive unit--- The ones I've talked to that own them say that the boat dose hadle better because of the weight being lower. They to were using their boats commercially but they were having trouble with different drivers not doing a good job and sinking boats once they went to the low drive that driver has not sunk a boat as of the last time I spoke with them.--- A tour guide out of ?? Louisiana ?? I could get his contact info if you want it -- (do a PM) The only big drawback is the $$$$ they run around 6k more than regular reduction ----- If you want go to my web and I can give you a price on a new Alumitech boat
 
So Waterthunder, your recomendation would be lesser clearance for deckovers to a max of 1.5"? Other post's on the subject recomend 4 to 6 inches :? . I get the idea of having the prop inside an open boat is not to pick up stuff at the bottom of the hull so it sounds the deckover guys have to be more diligent as to stuff on deck and briefing passengers as to loose items but I also see prop inside of boat as a waste of thrust. :roll: Do you recomend some kind of water diverting rail at the base of the cage on deckovers? The Palm Beach look so small at the back, I would think its forward momentum that keeps the props dry on those! :twisted:
 
BPS, you're right, some things are covered over and over, but I don't think this topic is one of them.

Of all the threads on this forum, about 10% or probably less are actually about how to set up a boat.

I'd love to read more about engine stands so that when mine isn't working right, I'll know why.

Thunder and others, please tell us more!
 
Red one of the things that I've learned about engine stands from many sources is that light weight but strong is best. Corner bracing is strong and well worth the time to put it in. Plus in the airboating application to have a support from the back engine mount down to the leg of the high drivers stand at the deck in a straight line to transfer the push of the prop towards the aft. center area of the boat. I know that I sure don't want that 550hp behind me to pass my seat with me in it. And to check your welds every time you are shut down. Finding a crack before it becomes a brake can be a blessing in disguise.
 
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