[predavolk]

Originally Posted by Brag

I confirm that one

I think you get marginally, 5% or less, better mileage out of 7 knots in a IXB. Even if true, I prefer the higher speed setting of 8 knots. 8 knots is enough to get you to North America with plenty of fuel left to boot around with. Honestly though, this should be pretty easy to figure out for yourself. Run a straight line of reasonable length as your course, preferably in calm weather, and ask your navigator how far you can go at your current speed. Adjust your speed until you get the longest distance. That's the most fuel efficient speed for your boat.