11-23-2021, 05:12 PM
I keep copious records for any number of reasons. One of them is so I can consider the overall health of my motors through fuel burn numbers. I have some interesting numbers this year and am curious what you all think...
Boat: '99 4000 Express with CAT 3208's (435hp)
Cruise: She seems most comfortable at 2300RPM which consistently gives me 19-20kts. According to the performance report for this boat, I should be a hair faster (23kts) at that RPM, but have always written it off to age of the boat, stuff, varying fuel/water levels, etc.
MPG/GPH: Interestingly, for the RPM/speed I mentioned above, my average GPH for the season (21.5) is a bit less than what the performance report says it should be (29.6). I would consider this good. But my average MPG for the season (0.56) is also less than what the performance report says it should be (0.89).
Thoughts? I would expect MPG and GPH to be high or low together, not spread in different directions. Curious what you all think.
Boat: '99 4000 Express with CAT 3208's (435hp)
Cruise: She seems most comfortable at 2300RPM which consistently gives me 19-20kts. According to the performance report for this boat, I should be a hair faster (23kts) at that RPM, but have always written it off to age of the boat, stuff, varying fuel/water levels, etc.
MPG/GPH: Interestingly, for the RPM/speed I mentioned above, my average GPH for the season (21.5) is a bit less than what the performance report says it should be (29.6). I would consider this good. But my average MPG for the season (0.56) is also less than what the performance report says it should be (0.89).
Thoughts? I would expect MPG and GPH to be high or low together, not spread in different directions. Curious what you all think.
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