by idvette » Oct 08, 2013 6:30 am
The bouncing is porpoising, your boat and motor are fighting each other. The hull is trying to produce lift, but can't, it's either being let down by not enough speed or forced back down by the motor. A drag plate, as mentioned above will help, but it's still going to happen a bit at lower speeds. Play with trim and throttle through it. My boat is only a foot longer, with a 200 Merc on the back, I've had porpoising issues for years. The drag plate nearly eliminated it. It used to porpoise from 30 to almost 60 mph, now it only does it between 40 and 50ish, but now I can drive through it much easier, before I was timing the bouce and nailing the throttle to get out of it lol. Now with a little throttle and trim it settles down.
ABSOLUTELY DO NOT mount a fuel tank in the bow. You can add ballast, I use sand bags, but not a tank. The behaviour of the boat will change as you use fuel, you don't want that. Static ballast is what you would want if you go that route.
You're in Toronto?? You should check out fast boats canada, and high performance boats canada, both websites have a lot of great guys that can help out. We also plan meets throughout the year, I just posted pictures from last weekend's run from Bewdley to Peterorough. The best thing you can do is come out, check out some boats, talk to the owners, and get an idea of what you may need. Good luck!
[ Post made via iPhone ]
The bouncing is porpoising, your boat and motor are fighting each other. The hull is trying to produce lift, but can't, it's either being let down by not enough speed or forced back down by the motor. A drag plate, as mentioned above will help, but it's still going to happen a bit at lower speeds. Play with trim and throttle through it. My boat is only a foot longer, with a 200 Merc on the back, I've had porpoising issues for years. The drag plate nearly eliminated it. It used to porpoise from 30 to almost 60 mph, now it only does it between 40 and 50ish, but now I can drive through it much easier, before I was timing the bouce and nailing the throttle to get out of it lol. Now with a little throttle and trim it settles down.
ABSOLUTELY DO NOT mount a fuel tank in the bow. You can add ballast, I use sand bags, but not a tank. The behaviour of the boat will change as you use fuel, you don't want that. Static ballast is what you would want if you go that route.
You're in Toronto?? You should check out fast boats canada, and high performance boats canada, both websites have a lot of great guys that can help out. We also plan meets throughout the year, I just posted pictures from last weekend's run from Bewdley to Peterorough. The best thing you can do is come out, check out some boats, talk to the owners, and get an idea of what you may need. Good luck!
[size=75][b][i][ Post made via iPhone ][/i][/b][/size] [img]http://www.hydrostreamforums.com/images/mobile/iPhone.png[/img]