Formula boat porpoising

erick26 · 10-04-2019, 07:13 AM

For what it’s worth I have a 2015 290 with twins and I have experienced this in the past. I will say the boat drives beautifully with drives all the way down all the time, but I feel there was a bit of extra drag and probably sacrificing a bit of fuel efficiency. I could very slightly trim up (maybe 10%) without issues but didn’t feel I was getting full benefit but it drove fine as well. If I went a little higher (20-30%) it would porpoise and not drove well. I went out with a friend one day and started playing around and went to 50-60% and it drove fantastic. It was much higher than I thought was logical but it literally floated on water and cut through everything with minimal slam on the hull even in choppy conditions. Don’t be afraid to play around - we were at about 3200 RPM/30ish MPH in this case which is a great cruising speed for the boat. Hope this helps a little.

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XCR-700 · 10-04-2019, 10:19 AM

Quote:

Originally Posted by erick26

For what it’s worth I have a 2015 290 with twins and I have experienced this in the past. I will say the boat drives beautifully with drives all the way down all the time, but I feel there was a bit of extra drag and probably sacrificing a bit of fuel efficiency. I could very slightly trim up (maybe 10%) without issues but didn’t feel I was getting full benefit but it drove fine as well. If I went a little higher (20-30%) it would porpoise and not drove well. I went out with a friend one day and started playing around and went to 50-60% and it drove fantastic. It was much higher than I thought was logical but it literally floated on water and cut through everything with minimal slam on the hull even in choppy conditions. Don’t be afraid to play around - we were at about 3200 RPM/30ish MPH in this case which is a great cruising speed for the boat. Hope this helps a little.

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Interesting, I would have never expected it to respond better at a point of trim past where it porpoised.

As several folks here have suggested, I still need to spend more time getting to know it and trying different combinations.

Based on your experience, I may need to think beyond my previous experience which told me to stop adjusting the trim level up when I started to experience porpoising.

Sounds like a good reason to get in more seat time next season

10-04-2019, 07:13 AM	#1
erick26 Member Join Date: Aug 2016 Posts: 21 Thanks: 143 Thanked 18 Times in 7 Posts	For what it’s worth I have a 2015 290 with twins and I have experienced this in the past. I will say the boat drives beautifully with drives all the way down all the time, but I feel there was a bit of extra drag and probably sacrificing a bit of fuel efficiency. I could very slightly trim up (maybe 10%) without issues but didn’t feel I was getting full benefit but it drove fine as well. If I went a little higher (20-30%) it would porpoise and not drove well. I went out with a friend one day and started playing around and went to 50-60% and it drove fantastic. It was much higher than I thought was logical but it literally floated on water and cut through everything with minimal slam on the hull even in choppy conditions. Don’t be afraid to play around - we were at about 3200 RPM/30ish MPH in this case which is a great cruising speed for the boat. Hope this helps a little. Sent from my iPhone using Tapatalk

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XCR-700 (10-04-2019)