Captains choice on a jet boat?

[mud duck]

Has anyone ever rigged up something similar to a Captains Choice option on a jet boat? It might only have "Through Transom Exhaust" above and below the water line as options, but that would at least be quieter around docks and boat ramps. And I know it would still be loud at WOT, but maybe that would be okay. Or, has anyone pushed the exhaust straight down through the hull on a jet boat? This might screw up the jet intake unless you placed the exhaust ports out to the sides a little bit.
I am just looking at how I can quiet down my boat when I choose to, yet open her up with no restrictions as I please. Or does the change in back presure mess up the engine in some way?
Your thoughts..................

[mud duck]

Well, I guess this answers my question, no one apparently has done this before. :(

[Jordy]

I think if you ran it out from under the boat you'd be creating a whole big mess of different problems depending on where you put it. At speed you could almost force water back up into the exhaust depending on where they were on the bottom, and certainly if you came off plane you'd have a surge of water coming up through your exhaust. As far as a system with about and below water thru transom exits, I'm thinking the gains would be minimal for the nightmare of a monster exhaust system you'd end up with. Just run it below water for when your idling around because once you're on plane they're above water anyway right?
Just my $.02

[mud duck]

Thanks for your input. I bet those air pumps, lines & Y-valve flappers are trouble pron too. It may be just another big headache.
Question; If I moved the current exhaust down below the water line, what do I do with the holes left by the old exhaust tips? Or perhaps I leave them alone, just for show purposes.
Oh, it never ends. :D

[Cheap Thrills]

either glass the holes back in or get a good supply of high performance stickers to cover em up with I hear they're good for another 10 mph each. :D
C.T. :wink:

[572Daytona]

Originally posted by mud duck
Question; If I moved the current exhaust down below the water line, what do I do with the holes left by the old exhaust tips? Or perhaps I leave them alone, just for show purposes.
Oh, it never ends. :D
My boat was switched from TT's to OT's and they installed plates to cover the holes, I suspect Rex Marine would sell something like that
http://home.alltel.net/jthieme/Dscn0578e.jpg

[Mohavekid]

Check this out.
I've ridden in a boat with this exhaust and it is much more quiet than regular thru transom exhaust. I'm sure there is some performance loss, but the boat I rode in seemed to run very well for a stock motored boat.
http://www.boicejet.com/exhaust.html

[mud duck]

Mohavekid, I had made something similar to those Boice exhaust extentions out of PVC pipe for my old Taylor. However, when I attempted to use them on my Ultra, the engine just blew them off the back. Now if I bolted them right to the hull transom or to the existing exhaust tips they would be much more secure. I actually like the looks better of that welded unit Boice has. Thanks for the info.
572Daytona, You are correct sir. I found that Rex does sell those polished disks for plugging old exhuast holes. Thanks.
Thanks for all your help guys!!! :D