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checkmate76
06-19-2002, 10:25 AM
Iv'e got an 18 ft checkmate berkeley JG.
My problem is at speeds around 60-65 the boat is porpoising pretty bad. I really can't afford a diverter yet, but was wondering if a wedge or two would help stop this porpoising.
will a wedge affect planing out?
4º or 8º?

Blown Sleek
06-19-2002, 10:29 AM
If you put the wedge thrusting down it will plane better (quicker) loosing top end most likely but loosing porpoise cause the deck will be plowing. With the nozel facing upward planing will be slower (more bow rise) and the top speed will be most likely higher due to less boat in the water (to a certain extent) The porpoise will only occure if you have to little power to cary the weight of the boat. ETC ETC.

checkmate76
06-19-2002, 12:39 PM
I'm probably running about 375-400 hp. I was told a diverter(up) would stop the porposing because of less wetted surface?
I just want to know if installing this wedge(thrust up) will give me the same result as a diverter and stop the porpoising or lessen it a bit.

Blown Sleek
06-19-2002, 01:01 PM
Hard to say. My boat porpoises real bad until about 60 with the jetovator up then the boat starts to cary the front well. If I pull the jetovator up prior to this speed the boat gets air then falls back in repeatedly (porpoises) I constantly play with it! Larger day cruisers etc I think are much less susceptible. Small tunnel boats most sussep. For skiing I would definitely leave it down.

checkmate76
06-21-2002, 08:06 AM
Thanks Blown Sleek for your advice!
well I don't pull any skiers and my boat is a shallow V-bottom (average weight).
Can ANYBODY tell me if a wedge will stop my porpoising?
maybe I'll just have to buy a couple and see, but I would rather find out first than go through the trouble.
[This message has been edited by checkmate76 (edited June 21, 2002).]

wsm9808
06-21-2002, 08:32 PM
I dont know it anyone can give you a yes or no answer to your question, every set up is differant. you have to consider weight of hull, power, wieght distrabution, pump set back, ride plate,ondition of boats bottom etc, etc. A wedge might make one boat smooth out and another react worse. Unfortionaly it is just one of those things you will have to experiment with or go with a Place divertor.