FSPROPELLER

C-Spray:

100% correct, Volvo does an outstanding job of complete system design, from noise to efficiency to vibration. Very very well done propulsion systems.

obads 31

What about GM's new Duramax 6600 ??? I've been thinking that a cloosed cooling system on this motor with a few computer upgrades offered for trucks, 450 HP and 800 or900 ft lbs and this would be a sweet motor for my 26' wellcraft. It now has a 72C velvet drive V-drive hooked to an Arneson #6 with 350 HP SB I think $$$ wise and power wise the Duramax would be way ahead of a built 406 to 454 SB . the tricky part might be the right prop for the low [3200/3500] RPM This trans is usually behind Big blocks so it should take the power. The trans is 1.5 to 1 any thoughts on how this '81 hull will perform??? What prop would you use ??? thanks andrewmasonsr

Sonic30ss

Take a look at this....www.marinedieselusa.com
I don't have anymore info than what is on the site but it really looks promising. The screw supercharger, is a great way to build the torque down low and fast. They don't list a torque rating for the 400hp but it should be up there...

FSPROPELLER

The company in Stillwater, OK that Sonic mentioned is a cooperation with the guys in sweden. I met both of those guys in Miami, they are currently working on their formal emissions certification which is due by the beginning of Jan05 for recreational use.

They feel that the AM General 6.5 will meet emissions not by electronic fuel management but because of the mechanically forced air. Typically these engines are dirty until the turbo kicks in. The supercharger solves that but how much is lost at the top end? Volvo used a clutch to switch from the charger to the turbo once the engine spooled up.

I agree with andrewmasonsr that the Duramax would be an ideal engine. Right now it seems they are all going to the pickups and there may be other auto priorities prior to marinization (Suburban??)

I suppose a guy could find one in a wrecked vehicle but the wet exhaust manifold would have to be cast and the chip would have to be designed.

cobra marty

I like that WSD drive pictured above. Now if they can put the trans in the ext. box like the arneson-bravo conversion, that would be the ticket. Broken bravo drives problem solved.

cobra860

I have a marinediesel in my boat and are quite happy with it.

Hee you see a link to a scarab with 2 hammerhead 300hp engines a dbd surfase drive

http://www.dbdmarine.com/gallery/index.htm

there is a video of this boat. it does 70 knots with 2 hammerheads.

Sonic30ss

Cobra860- How about some more info on that engine..
Fuel consumption, mantainance, ect.
Thanks

rtaylor

There is something to this. It seems to make a lot of sense, the diesel application.

cobra860

Sonic 30 ss.

I had 100 running hrs on the engine last summer.

the only problem I had was that one of the motormount broke off, the reason was that the bolts was not tigthen properly so the motormount got lose and finaly broke off.

I replaced them with original mercruiser v8 cast iron mount and aplyed locktite 270 on the bolts.

Oilfilters and oil is to be replaced every 50hrs
oil on the compressor is to be replaced every 250 hrs.

The diesel cost in Norway 3$ a gallon and I used aprox
1100$ in diesel last summer.

so that will be 11$ a hour running time.

For me that is cheap compared to a gasoline wich is aprox 5$ a gallon

Sonic30ss

Cobra... How hard do you run that engine, if my calculations are correct you burn less than 4 gallons /hour. thats unbeliveable!!
Those 400 horse Tigersharks are starting to look pretty good. Hell even if they burned 10 gph, that would be great. If I may ask what was the cost?
Do you have a transom exhaust if so what does it sound like?