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cb
 
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I have an '04 270hp VolvoPenta 5.0 on a 21.5' FourWinns Funship (4200 lb
boat) w/ 19" prop... turns 5000 rpm at WOT and gets to 51 mph with a
medium load... exactly matches what the dealer and manuals say it
should. I cruise at about 27-28 mph at 3000 rpm.

You dont say what speed you see at WOT. I'd suggest trying the next
higher pitch prop, should drop your R's by about 150-200 and maybe add a
couple mph.
....cb


David Patnaude wrote:
We purchased a 2004 Sea Ray Sundeck 240 at the end of last season and just
put it back in the water last weekend. We were pretty easy on it last year
and just got enough hours on the engine to get through the 20 hour break-in
period.

Now, we are pushing the boat a bit harder and the RPM at full throttle
seems too high to me. Our previous boat was a 1990 with the 5.7L 260 hp
engine, so I am not sure if things have changed.

This engine is the 350 Magnum MPI with Bravo III drive producing 300 hp. At
full throttle, the engine is turning 5200 rpm and the speed is not that
great. Also, compared to my previous boats, the RPM vs. speed is quite
different. The older boats had a very close correlation between the RPM and
speed with 3000 RPM being very close to 30 MPH. This boat, the RPM is much
higher than the speed, probably 1000 RPM higher than the speed.

Do you think the boat is mis-propped?

I am going in soon for a steering cable problem and wanted to get some
opinions on this issue too.

Thanks,
Dave