502stang

Where do you get the water to fill your tank? Do you have a separate pickup? Do you come off of your water pump? It seems like a ballast tank or maybe a couple in different locations can be a good thing for a high performance boat.

PARADOX

Just a quick note to all you "ballancer" guys.

Remeber where your fuel tank is and how much fuel you have. A full tank boat may have a CG in a different place then when it's 1/4 full. Also the hull design is critical. A steped or double step boat may need to be balanced different then a "no step" hull. A 38' boat with a relatively "straight" bottom (keel) will need the CG in a different location (may not work with the 25% rule) then a "curved" hull. A "ballast" system will help you in different speeds, but the best thing is to experiment and see what is the boat and you are at the best CG comfort level.

smiklos@sunprint

iTrader: (1)

We use engine coolant water after the engine.
Steve

Wahoo ATV

I believe where you set the CG should also take into account if you have a stepped boat. For example on my fountain I want additional weight in the back so my cg is set right at the first step from the transom. Moving it forward would have a significant effect on turning.

502stang

I agree totally...It would all center around the exact boat that you are talking about and the conditions that your would be running in. My boat has a pad but no steps so I need to get the bow up to free the hull. If you count on the prop to do all the work to get it up the boat does not take a set and get stable at speed. Look at those Cat Killer boats...they run like a bass boat back on the pad but set there just as stable as can be. I have had several people that have told me that Reggie Fountain is always talking about balance in his boats.

bcarpman

I'd love to hear more about how to impliment a balast tank: adding and removing water, do you need to put something in to control the water going in? What sort of pump did you use to remove the water? What do you build the talk out of? Anyone try a bladder of any sort instead of a solid tank?

Any details would be appreciated.

My boat runs bow down and I'm trying to fix the hull to get the bow out of the water when it's smooth, but I've noticed that in rough water, the ride is a LOT smoother when someone is passed out on the v-berth. It would really be nice to add a couple hundred pounds when max speed isn't an issue but a smooth ride is.

CcanDo

Here are some pics of our current set-up

fastdonzi

That looks like someone is trying to add & dump water with nobody else seeing

BenPerfected

Cat,
Nice rigging job!! After seeing this, no post of my work ballast tank work will be forecoming...Polish the (2) 90's?
Ben

articfriends

iTrader: (1)

Excellent topic,in the spring I also plan on finding the balance point on my boat front to rear. I am personally overweight and when I run my 4700 lb boat with no passengers in the rear seat it tends to bow steer violently at high speeds. It never seemed top do this before but I almost always have ran with rear seat passengers. lighter exhaust and cylinder heads have amplified my problem,I'm thinking Ineed to add about 100 lbs at very rear of boat. Example 1-blew a fuel pump fuse at almost 95 mph with rear seat passengers,transom settled down first and boat glided gently to a stop (had a hard time getting passengers to ride in boat again though).
Example 2-opposite-was running mid 90's with 1 passenger in front seat,started backing out of throttle and bowed dropped quickly causing boat to bow steer violently UNTIL azz end settled in.
My plan is to place weight equivilant to mine in driver seat area and same with pass seat area then sling boat to find cg fron to rear. Then I plan on mathematically calculating how much weight I need at rear of boat to be equivilant to about 400 lbs of rear seat passengers that seems to be what balances out my boat properly.
I/E-If 400 lbs 2 feet behind the fore/aft cg makes boat properly balanced,instead of adding 400 lbs there I would add 50 or 100 lbs further back to get the same effect without weighing boat down so much it hurts the ability to air out and reach top speed. I'm thinking a 80 lb water inflated ballast bag with a fill pump and a solenoid drain placed in the molded hollow swim platform my boat has. Great thread,keep the ideas coming,Smitty