89 390 EC Fuel burn?

[sr330daguy]

7.4 gassers anyone have info on consumption vs speed ?Thanks in advance.

 

[fwebster]

Figure on 18-20 kts burning between 32-36 gph....lots of variables though. Carbureted or EFI repowers, 3 blade or 4 blade props, clean bottom, a little slime, or are you dragging around trees under the boat, full fuel/water or light, how many full grown humans are onboard, etc. etc. The gas 390EC is very load and bottom condition sensitive.

 

[sprink56]

Figure on 18-20 kts burning between 32-36 gph....lots of variables though. Carbureted or EFI repowers, 3 blade or 4 blade props, clean bottom, a little slime, or are you dragging around trees under the boat, full fuel/water or light, how many full grown humans are onboard, etc. etc. The gas 390EC is very load and bottom condition sensitive.

I was surprised how much a few "mini-barnacles" growing on the props affected mine. When I hauled it for a bottom job before I sold it it would not quite pull 24 knots and would just crack 4000 RPM with a light load. The bottom was reasonably clean but there were plenty of critters on the props. With a fresh bottom job and clean props it made 29 knots and turned 4600 RPM with the same load....very sensitive to prop critters.