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-   -   You're the experts - Suggestions on Diesel Go-Fast... (https://www.offshoreonly.com/forums/general-boating-discussion/213114-youre-experts-suggestions-diesel-go-fast.html)

poddy 07-21-2009 04:13 AM


Originally Posted by Jassman (Post 2914169)
6 blade Herings 74.6mph

diameter and pitch or is that classified?

J Arruda 07-21-2009 10:58 AM

3 Attachment(s)

Originally Posted by Catmando (Post 2911943)
I think you should take a look at turbines. John Arruda at www.turbinemarine,com put a pair of his 1450hp turbines in an 18,000lb 51' Outerlimits V bottom and it's running over 130 with Merc 6 drives. He has solved a lot of problems with turbines in the Marine environment, especially exhaust heat with water-jacketed exhaust. One problem with turbines is they burn as much fuel at idle as they do at WOT.

Eliminator boats built a 12,500lb 43' V with staggered 480hp Cummins-Mercruiser diesels that is running close to 75mph. If that boat(Scarab) had the Fountain bottom it would run well over 80.

One way to wring more speed out of a diesel is multispeed transmissions. Weismann has developed transmissions from two to six speeds and they have also developed a Marine drive to handle the huge torque;

www.weismann.net


The latest out of my shop.
50' 9'6" beam 15,000 Ibs 130Mph at 200 gal per hr fuel burn. (28 gal per hr at iddle)
The boat is very quite (83Db), and has minimal heat signature as the exhaust is under water.
The boat is available for demo if needed. (And thank you catmando for the plug)

obrien 07-21-2009 10:50 PM

Team Taboo, the gears in that boat were from Twin Disc as you know. The mechanical shift on those gears didn't have a stop. ZF gears don't have that issue.

Blacklabmarine.. The company I work for built 3, 50' center console target drones for the Navy last year, and I will be doing 4 more this year. All 3 boats last year had Yanmar 480's with Arneson ASD8's. We were running twins in the hull and the last boat ran 67 mph full of fuel. however believe these hulls were in the 12-13k lb range rigged minus fuel. I verify that weight for you.

The boats we will be doing this year will have some minor changes and corrections in the mold that should put these boats over 70 mph.

We have been supplying the yanmar engines to nortec and so far cummins hasn't been able to touch the performance of our 480s.

I would say to put 3 480 asd 8 packages in that hull. As rick and joe pointed out, manuverability with the surface drives is just fine. I would stay away from Bmax or Konrad drives. They won't stay together behind the 440 or 480 yanmars.

29Firefox 07-22-2009 07:36 AM

Rumors of my demise were BS
 

Originally Posted by HabanaJoe (Post 2913192)
29firefox - nice to hear from you again

I know what cable play is but have to say never, never, never seen that do any damage. You know we ran Fabio's boats and our own. The biggest thing was - keep everything mechanical no electric or hydraulic controls/systems unless there was no other option. Granted electronics have evolved over the last 20 years and today are more reilable than a mechanical connection.

But it seems to me and I'm not wanting to fight with people on this but cable play on a little 40' boat with straight runs to the engine room is poor installation more than anything.

It's also a matter of evolution of the engines & gear boxes too. Some packages just don't have any levers on em anywhere to hook up a morse cable to:eek:
Some markets demand morse cable hook up. Komatsu went so far as to design their electronically controlled engines to use a morse cable. Yup the morse cable comes down to engine room and hook up to a lever on the side of the ECM box:lolhit:
My previous post I mentioned tunable shift lag and multi harness routing but I forgot to mention was synchronization or "Single lever Throttle control" One of my proudest moments of red neck engineering was when I used two Glendining boxes to daisy chain a set of triple 16V92s so they could do the single lever thang:ernaehrung004:
You also hit the nail on the head. Most cable problems are from chitty installation.:bong:
Also for the koolaid drinkers that toot Yanmar's flute. I live and work in Yanmar's homeland and when ever a customer goes Komatsu they never go back. :cuqui:
.................................................. ...................................yanmar

obrien 07-22-2009 09:24 AM


Originally Posted by 29Firefox (Post 2915402)
It's also a matter of evolution of the engines & gear boxes too. Some packages just don't have any levers on em anywhere to hook up a morse cable to:eek:
Some markets demand morse cable hook up. Komatsu went so far as to design their electronically controlled engines to use a morse cable. Yup the morse cable comes down to engine room and hook up to a lever on the side of the ECM box:lolhit:
My previous post I mentioned tunable shift lag and multi harness routing but I forgot to mention was synchronization or "Single lever Throttle control" One of my proudest moments of red neck engineering was when I used two Glendining boxes to daisy chain a set of triple 16V92s so they could do the single lever thang:ernaehrung004:
You also hit the nail on the head. Most cable problems are from chitty installation.:bong:
Also for the koolaid drinkers that toot Yanmar's flute. I live and work in Yanmar's homeland and when ever a customer goes Komatsu they never go back. :cuqui:
.................................................. ...................................yanmar


You may not like them, but they have their place. There must be a good reason why almost every nortec diesel boat has them.

29Firefox 07-22-2009 09:41 AM

Just some basics
 
This is from real world experience. Ya all are looking at engines that are too small. To get rock solid performance in the 50 knot and over patrol boat range you need at least a horsepower total of 1500 ponies or better. The gold standard in the real world is the 1000 hp Man. The Man will out perform the Cat & Komatsu engines on top end but Cat & Komatsu can out cruise Man and the Cat would out top end the Komatsu but the Komatsu will out cruise the Cat. Running gun battles take place at cruise speed not at top end. Fabio helped design the Seateks but when it came time to power his own boats he put Cat C-15s in em. The Seateks will out top end the Cats but the Cats will out cruise the Seateks. Reliability & the ability to have good "heat balance" over time. Those things are what close the deal. Don't get tunnel vision an which will give you the highest top end unless it can hold the output for at least 8 hours straight.:p

29Firefox 07-22-2009 09:48 AM


Originally Posted by obrien (Post 2915485)
You may not like them, but they have their place. There must be a good reason why almost every nortec diesel boat has them.

Yanmar has the best damn salesmen:cool:

Jassman 07-22-2009 01:31 PM


Originally Posted by poddy (Post 2914461)
diameter and pitch or is that classified?


18 x 31 classified..LOL

Jassman 07-22-2009 01:49 PM


Originally Posted by 29Firefox (Post 2915503)
This is from real world experience. Ya all are looking at engines that are too small. To get rock solid performance in the 50 knot and over patrol boat range you need at least a horsepower total of 1500 ponies or better. The gold standard in the real world is the 1000 hp Man. The Man will out perform the Cat & Komatsu engines on top end but Cat & Komatsu can out cruise Man and the Cat would out top end the Komatsu but the Komatsu will out cruise the Cat. Running gun battles take place at cruise speed not at top end. Fabio helped design the Seateks but when it came time to power his own boats he put Cat C-15s in em. The Seateks will out top end the Cats but the Cats will out cruise the Seateks. Reliability & the ability to have good "heat balance" over time. Those things are what close the deal. Don't get tunnel vision an which will give you the highest top end unless it can hold the output for at least 8 hours straight.:p

Part of what you are saying is true..but factor in weight/size to power/torque ratio and the Yanmar just works....physics... and it works reliably on numerous Nor-Tech boats...that is why they use them....call backs in the marine or any business need to be at a minimum. My 43 Nor-tech weight is more than Jays new boat and the boat hit 74.6. This is not a hi tech bottom either with multiple steps..The same set up in Adib Mastry's 39 Nor-Tech boat..(owner of Yanmar in Sarasota)...did 80 gps and I believe high 81's on radar. My deal is.. if it aint broke..leave it the heck alone.. heres a video of that Yanmar boat..click the silver boat w/red strip..39 11,000. Nor-Tech

http://www.nor-techboats.com/videos.php

Catmando 07-22-2009 02:39 PM


Originally Posted by J Arruda (Post 2914698)
The latest out of my shop.
50' 9'6" beam 15,000 Ibs 130Mph at 200 gal per hr fuel burn. (28 gal per hr at iddle)
The boat is very quite (83Db), and has minimal heat signature as the exhaust is under water.
The boat is available for demo if needed. (And thank you catmando for the plug)

Ok now here's a rumor that has been debunked; I said turbines burn as much fuel at idle as at WOT. Thank you John for setting me straight. :)

Do you still have Warbird? I watch the youtube videos all the time. My favorite Nor-Tech. And what about Ken Cook's Hydrofoil? Has he delivered the boat yet?


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