What you are talking about is a cavatation reducer. First off, what kind of boat do you have, and what power? I would suggest if you do decide to get one, get your monies worth, and buy one from Jack at MPD in Costa Mesa. There $385 each but you will get what you pay for because that extra 85 bucks will make a night and day difference between one you would get else where verses one he works for you, so it actually does what it is suppose to do, reduce cavatation, not induce. I will see if I can get a photo of a worked one up here, but in the mean time, I would call Jack and talk to him because he can better explain this.
MPD (Marine Performance Designs)
(949) 631-2040
HBjet
[This message has been edited by HBjet (edited April 02, 2002).]