I've been running opti 150's for about three years now and I've always been surprised at how fuel efficient they are, and I do have a lead wrist! Nearly always under the litre per mile on a 6.5 Scorpion If I just cruise at thirty knots then it gets a lot cheaper.
We also Run a 225 on a 7.3 Gemini (thi sis a very heavy boat) and it maxes out at a touch under fifty knots and is sucking up 78 lph. This is on a par with Whiteshooz boat which is a Ribtec 7.5 with a Yammie 225 Fourstroke (Nice engine, by the way) and he pulls about the same at 47 - 50 knots
It is my understanding that you can overrev em as the ecu doesn't limit revs
Pettal are you having any Navman electronics on your boat. cos they do a very lovely interface to the Smart guages ( which are wicked!)
Here it comes again, I don't stand a chance
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