View Single Post
Old 08-25-2012, 11:56 AM   #19
FF
Guru
 
FF's Avatar
 
Join Date: Oct 2007
Posts: 22,553
Perhaps someone there has the power/rpm chart for your engine down rated with smaller injectors.

Injectors come from 40 -135 for many engines , perhaps yours would be happy with the smaller units.

The goal on a DD is to size the injectors so the engine is running at 60% or harder at the RPM you cruise at.

60% of rated power at max hp , or better will get most DD up in the 16 HP/gal range, about the best you can do.

Big hassle is this still may be too fast for the hull to be driven cheaply (SLx1.15)

Then all you can do is accept the poorer fuel efficiency at slow RPM ,
but enjoy the quiet and wait another 15,000 hours.

Many 6-71 (non turboed) are run at 1200RPM as prime gen sets , if you can get well loaded at that low RPM , you will be waiting till at least 20,000 , perhaps 30,000 shows on the clock.

Too bad CPP are so hard to retrofit.

There is always a set of cruising props , to get efficiency , but then you need an EGT to keep from overloading and a different pip on the tach for max RPM.
FF is offline   Reply With Quote