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SB
06-12-2001, 06:47 AM
There is a chart comparing jet efficiency to props in Yachting May 2001 p.28. Article states what we pretty much knew, jets are the most efficient propulsion, but only within a narrow rpm range. Maybe I'll send this over to Mercruiser. I don't want people to think I read Yachting all the time, but what the heck, a guy can dream. Just out of curiousity, anybody on this board running jets with twin diesels or turbines in a yacht costing over half a million? Heh, heh.

froggystyle
06-12-2001, 06:54 AM
Yeah, actually my Mead ride is a 84' Outer Banks with a set of Allison v-12's and pumps. Oh, wait. That was the dream with all the Sweedish bikini team on the boat giving out cocktails.
Never mind, I forgot, we're all poor. Except for River Dave with his Schiada http://free.***boat.net/ubb/biggrin.gif

spectras only
06-12-2001, 09:55 AM
SB, I don't own a 1/2 mil boat ,but a guy down from my house has a 38 Magnum with twin turbocharged Man Diesels and KaMaWa jets.No they are not efficient when that big,but safe to run in waters like British Columbia's rivers full of deadheads[from logging operations].This boat had shafts before [3" diameters]and used to get bent out of shape while running up to Rivers Inlet ,where he's got a fishing lodge.He spent 1/2 mil just to convert to jets.Awsome boats ,made in Florida by Ted Theodoli.By the way, our previous government {NDP}built some fast ferries with jets,capable carrying 300cars are for sale now,because it was a failure [reliability,fuel economy,500mil overbudgeted].Line up guys ,you may get one for 50 mil[bargain for the size]heh.
[This message has been edited by spectras only (edited June 12, 2001).]

mister460
06-12-2001, 02:32 PM
Hey Spectras! Been down to Washington lately? Just curious! I'll be coming up that way in August. We should go for a cruise! Unfortunately I'm gonna leave my boat down here in Cali. Way cheaper to fly! I'm starting the convert to a Berk drive today so wish me luck! Later! BTW, I thought that "fast ferry" thing got put in service! I remember it going over budget but last I heard (this was about 2 1/2 years ago, mind you) they were gonna keep it anyways. Because they'd already spent so much money on it y'know. Think they'd part them out? A jet bigger than my whole boat! I'd like to at least have one just so I could say that I did!

spectras only
06-12-2001, 03:47 PM
Mister ,those boats are mothballed right now so make your bid hehe.I should be around in august,give me a call in advance when you're going to be in Washington and we can hitch a ride in my boat.Also if you haven't been in the Okanagan you should make time to visit.I go there often in the summer,so you could tag along.

SeaSlut
06-12-2001, 05:11 PM
I know you guys must have seen this...
http://www.boats.dt.navy.mil/pg2/MK5.htm
http://www.chinfo.navy.mil/navpalib/factfile/ships/boat-mkv.html
Jets really do rule

spectras only
06-12-2001, 05:23 PM
Yes,wouldn't have to worry about dinging it.

froggystyle
06-14-2001, 09:39 PM
Seaslut, if you ever want a ride, let me know. Those SBU guys ferry me around for a living. Those boats are built to insert us with some Zodiacs. I've been in the MKV going 55 knots over some pretty good swells.

spectras only
06-14-2001, 10:03 PM
Froggy ,have you heard of Vospers or Thornycrafts? Those tubs go 85.

MellowYelloW
06-14-2001, 10:44 PM
you guys ever see the excursion boats on the rougue river...they start out in grants pass and go all the was down the river like 40 miles or something. some run dual motors and jets and they haul ass.

spectras only
06-14-2001, 11:14 PM
those boats have been around for decades,about 40 feet ,twin 454's and berks

turbo
06-18-2001, 06:36 PM
Heay fellas down here in new orleans they have a pt boat on display at a armed forces training station on lake pontchatrain, and guess what, it has twin berkleys sticking out the back.

spectras only
06-18-2001, 09:32 PM
I tought PT boats are around 75-85 feet,I wouldn't think twin berks would be efficient at that size,heh.

Jeff
06-19-2001, 03:00 AM
I wonder what size impeller its running AAAAAAAAAAAAAAAAAAAAA stainless lol. All kiding aside I worked with a fella that crewed on one back in WW II he told me his had a pair of V-12's Wouldn't that make a nice mill for say a 20 fter. :-)

spectras only
06-19-2001, 08:32 AM
Yeah .I'd like one of those R/R Merlins in my boat too,the weight would sink my boat though.

squirt
06-19-2001, 12:05 PM
Also had Hall-Scott's. How about 45 gal per hour each motor and thats not 92 octane gas, and since 75'long & 19' beam is a bit too hard on the old tow vehicle that would be dock prices for the fuel. But the bright side is there have been many stories about them being used as a ski boat. How would you like to cross that wake??????

spectras only
06-19-2001, 12:16 PM
20 years ago I bumped into a guy,who just purchased an 85 footer from San Diego,he converted it to a cruise boat,chartered it for a while and I think sold it back to an american.The PT's name was "Magnum Force".Anybody seen it down in Cal ?