Offset drive in narrow beam boat
#11
Originally Posted by IRONMAN
Center the drive and remount batteries or other things to make the boat run more level.
also drive height plays an important role as does speed.
so does bottom straightness. hooks , rockers , etc,,,, .
this is what is known as dialing in a boat. the more home work you do the better your work will come out.
#12
So, if I read this right.
I check the bottom for anything other than straight.
Establish an X dimension. I assume that higher is better as I can always ad spacers.
Then determine the boats center of gravity with the components moved to make the boat balanced?
We were thinking of a ballast tank in the nose just in case.
Here's the next question, can you make the boat too stiff? I wanted them to stiffen the midships bulkhead and make the forward V Berth bulkhead go all the way to the deck. Also we are making an enclosed engine room bulkhead. So the boat will have three complete bulkheads instead of two.
Thanks for your help. I think I might be boating one day
You don't have a month to spare do you??
Cheers,
Andy
I check the bottom for anything other than straight.
Establish an X dimension. I assume that higher is better as I can always ad spacers.
Then determine the boats center of gravity with the components moved to make the boat balanced?
We were thinking of a ballast tank in the nose just in case.
Here's the next question, can you make the boat too stiff? I wanted them to stiffen the midships bulkhead and make the forward V Berth bulkhead go all the way to the deck. Also we are making an enclosed engine room bulkhead. So the boat will have three complete bulkheads instead of two.
Thanks for your help. I think I might be boating one day
You don't have a month to spare do you??Cheers,
Andy
#14
absolutely. offset will induce some less than desireable results , some of which you will not find until speed. as far as bulkheads i don't believe this will hurt. it will add structural rigidity, just don't over do it as to create a negative in-balance of strength.
as far as the x goes higher is not always better. you should contact the manufacturer to see where they have set the heights for best top speed. then maybe add an inch, so you can always space down. keeping in mind the c.g of the engine. you can mount the engine lower and use a shorty to keep the balance.
example: x is at 17. mount it at 16(lower engine c.g) use a 2"shorty. you'll have an 18x.
also, an experience I had with a single engine 30 super boat. 18x dimension. used shorty. bad torque over and rode on the bow as well because the drive had no leverage. spaced it down 1 1/2 straightened out and picked up the bow. increased leverage .no more side lean,also picked up 2 mph because of less wetted surface.
in short good c.g to start with is best, as is a straight bottom.
good luck
p.s as afr as a month to spare , $ is king
as far as the x goes higher is not always better. you should contact the manufacturer to see where they have set the heights for best top speed. then maybe add an inch, so you can always space down. keeping in mind the c.g of the engine. you can mount the engine lower and use a shorty to keep the balance.
example: x is at 17. mount it at 16(lower engine c.g) use a 2"shorty. you'll have an 18x.
also, an experience I had with a single engine 30 super boat. 18x dimension. used shorty. bad torque over and rode on the bow as well because the drive had no leverage. spaced it down 1 1/2 straightened out and picked up the bow. increased leverage .no more side lean,also picked up 2 mph because of less wetted surface.
in short good c.g to start with is best, as is a straight bottom.
good luck
p.s as afr as a month to spare , $ is king
#15
[QUOTE=monstaaa as far as a lefty just moving torque from right to left , no. imagine holding a righty prop and running the boat. the boat would try to rotate to the left.so with a lefty the opposite would happen therefore eliminating a torquing problem normally associated with right hand application's.[/QUOTE]
I'm imagining it and I see a boat with a righty prop torquing to port and a boat with a lefty prop torquing starboard?
I'm imagining it and I see a boat with a righty prop torquing to port and a boat with a lefty prop torquing starboard?
#16
i'm not imagining. i've tested this theory many times myself. with a few different manufacturers. kryptonite, superboat, donzi, activator, hustler, to name a few. water posseses a different law of physics.
so apply, if the boat has a hook or off x-dim. throw in different speeds and results become obvious.
so apply, if the boat has a hook or off x-dim. throw in different speeds and results become obvious.
#17
Now, for my next question.
Where is the correct CG. I would like to think that it would be right about where the driver would stand/sit. Is this the correct location with the boat loaded and everything positioned where it sould be?
Thanks for all you help.
Andy
Where is the correct CG. I would like to think that it would be right about where the driver would stand/sit. Is this the correct location with the boat loaded and everything positioned where it sould be?
Thanks for all you help.
Andy
#18
Registered
Joined: Nov 2003
Posts: 368
Likes: 2
From: Jamesport, New York
Play with the X center the drive do all hull balancing with internal weight changes, or you may induce something you can't fix without a lot of work. Personaly I would keep the X stock and go with a shorty, those results are more then well proven and not a myth in someones mind!
Phil
Phil
#19
Originally Posted by MOP
Play with the X center the drive do all hull balancing with internal weight changes, or you may induce something you can't fix without a lot of work. Personaly I would keep the X stock and go with a shorty, those results are more then well proven and not a myth in someones mind!
Phil
Phil
#20
Originally Posted by monstaaa
i'm not imagining. i've tested this theory many times myself. with a few different manufacturers. kryptonite, superboat, donzi, activator, hustler, to name a few. water posseses a different law of physics.
so apply, if the boat has a hook or off x-dim. throw in different speeds and results become obvious.
so apply, if the boat has a hook or off x-dim. throw in different speeds and results become obvious.



