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Old 12-15-2015, 01:34 PM   #17
Baker
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City: League City, Tx
Country: Texas
Vessel Model: Carver 356
Join Date: Oct 2007
Posts: 6,360
Quote:
Originally Posted by manyboats View Post
Amazing I'm OK w an overpowered boat and most others are questioning it.
Not my usual for those that don't know me.

If the engines were NA and 480hp I would be singing my usual song. But I really don't know much about tubocharged engines and assuming if they were ran at a 75% load they would wear much faster than a NA engine at 75% load. Also assuming most all people would run this boat at a 25 to 35% load re the 480hp. But if someone were to run this boat overdriven at 14 knots (assuming it could) I'd not be mak'in positive sounds about it. What does Yanmar say about a continous rating on these engines?

But like a turbo Cummins running just a bit into the turbo (40 to 50% load) should be fine. Due to the turbo I consider a big chunck of this power to be sort of artificial. Only useful for short periods of time. Tear into me if I'm wrong because I really don't know. And if these Yanmars are good to go at 80% load continously then I'm on the way over powered bandwagon. But also due to hull design these boats could be usually underpowered.
Look in my signature. I used to own one of those engines. They are very easily run at 75% continuously. What I would consider the sweet spot in my installation was 2800RPM on a 3300RPM engine(3100 continuous at 190hp...so the power curve is nowhere near linear...you gain 50hp in that last 200rpm). With that said, I think there is nothing terribly wrong with this application. Those engines will run perfectly happily outside of the boost. The boost comes on about 2200rpm....obviously depending on load but I am willing to be it would be right around there. Anyway, much like the 4236 is considered Perkins best engine....this engine is held in the same regard as it relates to Yanmars.
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Prairie 29...Perkins 4236...Sold
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Carver 356...T-Cummins 330B...FOR SALE
Meridian 411...T-Cummins 450C
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