I have read various posts about people operating their boat with the drive tucked under, or the trim tabs down, while on plane in normal weather. I was curious what effect it would have on my boat, so a month or so ago I gave it a try.
With the outdrive trimmed fully down, and the tabs fully down,
WOT RPM was 4200, GPS speed was 31.3.
I experienced some of the instability others have talked about, I had really never felt it before. Very stressful to me to operate the boat like this, as it seems I am abusing it by lugging the engine with too much added drag from wrong trim settings.
Then I trimmed the outdrive up to 'normal', which for me is just below where it would porpoise. So it is trimmed out a bit.
WOT RPM was 4400, speed 34.5.
Then I raised the tabs all the way up.
WOT RPM was 4600, speed 38.6.
This was with a single person on board, about 1/4 tank of fuel, and maybe 10 gallons of water; so lightly loaded.
With the outdrive trimmed fully down, and the tabs fully down,
WOT RPM was 4200, GPS speed was 31.3.
I experienced some of the instability others have talked about, I had really never felt it before. Very stressful to me to operate the boat like this, as it seems I am abusing it by lugging the engine with too much added drag from wrong trim settings.
Then I trimmed the outdrive up to 'normal', which for me is just below where it would porpoise. So it is trimmed out a bit.
WOT RPM was 4400, speed 34.5.
Then I raised the tabs all the way up.
WOT RPM was 4600, speed 38.6.
This was with a single person on board, about 1/4 tank of fuel, and maybe 10 gallons of water; so lightly loaded.
