My 330ec burns just about 33an hour at 3200rpm @25mph witg. Twin 454 @16600pnds I would expect you to burn 35 an hour but you have a little more hp probably turning a bigger wheel so u might be right around me. (Just my assumption) a lot of guys on here really pay attention and log there burn so u will get a much more accurate number soon
My 330ec burns just about 33an hour at 3200rpm @25mph witg. Twin 454 @16600pnds I would expect you to burn 35 an hour but you have a little more hp probably turning a bigger wheel so u might be right around me.
That's my guess as well. I'd be aiming for .75 sMPG.
My 454's are flirting with the 1,300 hour mark. The boat has been in the water for over 2 years. This season, my highly-accurate fuel meters are showing that with 1/3 fuel and 1/4 water in good seas, I can achieve .74 sMPG, after messing with throttles and tabs to reach the ideal settings. In past seasons, I haven't had to try quite so hard, but I suspect that being overdue for a haul-out and wash and bottom paint touch-up is taking a toll. My long-term average before installing meters was .72 The average has been creeping up since, and I always set site my sights on the holy grail of .75, which my display rounds to the false-but-awesome-feeling .8!
Factor your clean hull, the balance of your straight-shaft engines and (after break-in) your younger engines, your boat should outperform mine.
Funny you should ask about economy though, because as I was reading your trans thread, I thought to myself that you're an excellent candidate for fuel meters: not only will they give you valuable insight on "economy", but they can also give you a early indication of engine issues.
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