Seven Marine outboard 557 Hp

Latestarter1 said:
GM alloy block supercharged V8, ZF gear-train, big $$ ticket, color is your choice at no extra cost.

Any market in Europe for legal users of this power-plant, triple installations on Youtube!

http://www.seven-marine.com/
Click to expand...

that's some motor......!
compare the fuel consumtion to a similar diesel:
The giant 7 outboard which outputs 557hp uses 35gal/ hr at 4000 revs.
performance graph: http://www.seven-marine.com/motors/performance-and-efficiency/


Comparing that to the 530hp diesel Yanmar at 2500 cruise uses 25gsl/hr....
http://www.yanmarmarine.eu/theme/ya...atasheet/English/Yanmar-6CX-530 datasheet.pdf

..about 50% more fuel, whereas the Suzuki 300hp leanburn exactly matches the Volvo diesel 300 hp at about 6.5gsls /hr.

Yanks still don't bother about fuel consumtion!
 
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I like O/Bs in many respects, but this is one of those "only in America" things, imho.
Just had a quick look at the specs, comparing them with the Yam 300hp V6.
FOUR Yams would weigh just 70kg more than TWO Seven Marine, giving almost 100hp MORE overall - not to mention that Yam rated power is at prop shaft, whilst this Seven Marine is not specified.
I suspect that the 4 Yams wouldn't cost more than the 2 monsters, either.
Now, with the Yam setup, you would have 4 very reliable NA engines, and a setup whose redundancy is amazing - depending on the boat, it might be possible to keep cruising at planing speed with just 2 out of 4 engines running.
With the Seven setup, you would have 2 supercharged blocks put together from someone whose service network just doesn't exist, and a barely get-home setup in case one engine gets disabled for any reason.
Talk about no brainer...
 
MapisM said:
I like O/Bs in many respects, but this is one of those "only in America" things, imho.
Just had a quick look at the specs, comparing them with the Yam 300hp V6.
FOUR Yams would weigh just 70kg more than TWO Seven Marine, giving almost 100hp MORE overall - not to mention that Yam rated power is at prop shaft, whilst this Seven Marine is not specified.
I suspect that the 4 Yams wouldn't cost more than the 2 monsters, either.
Now, with the Yam setup, you would have 4 very reliable NA engines, and a setup whose redundancy is amazing - depending on the boat, it might be possible to keep cruising at planing speed with just 2 out of 4 engines running.
With the Seven setup, you would have 2 supercharged blocks put together from someone whose service network just doesn't exist, and a barely get-home setup in case one engine gets disabled for any reason.
Talk about no brainer...
Click to expand...


Now with hulls being designed for these monster OB's weighing 1/2ton each, and with the bottom legs able to cope with massive the torque and hp, it's time to bring on diesel Ob's in the 300 hp-400hp range.

No commercial operations use outdrives, so a big diesel outboard has to be a no brainer, compared with the complexities of installing an inboard setup......

seem to remember some outfit in Sweden is developing something along those lines.
 
Wasn't there someone developing a 200 & 300 HP Diesel Outboard....

Never heard any more from them as I recall

Just found it was Maritime Engineering Group - 3.0l common rail diesel of 175, 225 & 300HP

But last I can find on the net is 2009....

Does anyone know, did this die the death, and if so, surely the times come for one of the big outboard manufacturers to look into what's gotta be a MASSIVE hole in the market....

I mean come on - 300 hp diesel outboard on a 25 footer - that's gotta be attractive...
 
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rustybarge said:
that's some motor......!
compare the fuel consumtion to a similar diesel:
The giant 7 outboard which outputs 557hp uses 35gal/ hr at 4000 revs.
performance graph: http://www.seven-marine.com/motors/performance-and-efficiency/


Comparing that to the 530hp diesel Yanmar at 2500 cruise uses 25gsl/hr....
http://www.yanmarmarine.eu/theme/ya...atasheet/English/Yanmar-6CX-530 datasheet.pdf

..about 50% more fuel, whereas the Suzuki 300hp leanburn exactly matches the Volvo diesel 300 hp at about 6.5gsls /hr.

Yanks still don't bother about fuel consumtion!
Click to expand...

Bear in mind those are titchy US gallons whereas Yanmar are using imperial gallons.
 
penfold said:
Bear in mind those are titchy US gallons whereas Yanmar are using imperial gallons.
Click to expand...

And the Yanmar weighs 837kg without a gearbox - you are hardly likely to be hanging a pair of those off your transom! so you'll be wasting all that efficiency through 'draggy' shafts, way fewer real world MPG I reckon
 
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