To notch or not to notch?
#1
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Hi!
I have a Phantom 25 offshore hull with a Promax 300. It runs relative wet and need a lot of positive trim .Top speed 78 mph in spring spinning a Tempest 26 at 6.150 rpms. In summer 76 mph at 6.050 rpms.
Currently I run 7,5 inches setback. I have tried 12 inches of setback. The boat was faster, but tailheavy in high seas (despite trimtank in front). Best overall result has been 7,5 inches setback - CMC powerlift + spacers.
When I ran 12 inches I used a seperate stainless steel bracket + the CMC powerlift. Weight in all 170 lbs... in steel.
The boat is a 1985 model and has a classic 24 degree V bottom without a notch. The new 24 feet version has a notched transom of 4-5 inches deep. I consider to cut out a notched transom on the old Phantom. What do you think about this? Then I get easier bowlift without adding extra weight aft. Any ideas would be appreciated.
Cheers and thanks, Toffen -Norway
I have a Phantom 25 offshore hull with a Promax 300. It runs relative wet and need a lot of positive trim .Top speed 78 mph in spring spinning a Tempest 26 at 6.150 rpms. In summer 76 mph at 6.050 rpms.
Currently I run 7,5 inches setback. I have tried 12 inches of setback. The boat was faster, but tailheavy in high seas (despite trimtank in front). Best overall result has been 7,5 inches setback - CMC powerlift + spacers.
When I ran 12 inches I used a seperate stainless steel bracket + the CMC powerlift. Weight in all 170 lbs... in steel.
The boat is a 1985 model and has a classic 24 degree V bottom without a notch. The new 24 feet version has a notched transom of 4-5 inches deep. I consider to cut out a notched transom on the old Phantom. What do you think about this? Then I get easier bowlift without adding extra weight aft. Any ideas would be appreciated.
Cheers and thanks, Toffen -Norway
#2
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I wouldn't notch. You've got an outboard on a jackplate.
Raising that motor up and down to find the sweet spot is your best tool. That along with the setback possibilities should give you the best possible position for that gearcase to be at.
You are running pretty good for a heavy deep vee with 300 hp.
Experiment with props. You're only going to get so much from your setup. Is the bottom straight? Is there hook?
Raising that motor up and down to find the sweet spot is your best tool. That along with the setback possibilities should give you the best possible position for that gearcase to be at.
You are running pretty good for a heavy deep vee with 300 hp.
Experiment with props. You're only going to get so much from your setup. Is the bottom straight? Is there hook?
#3
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Hi!
Thanks for replies. The bottom is straight and sharp. It was blueprinted 2 years ago. I am also uncertain whether the crusing abilities will be affected if I notch. I have decided to play with a lighter and larger powerlift to see if this work better than the stainless steel setup I tried last time (CMC powerlift in stainless steel + stainless steel bracket = 170 lbs...).
Cheers and A Happy New Year from Norway!
Toffen
Thanks for replies. The bottom is straight and sharp. It was blueprinted 2 years ago. I am also uncertain whether the crusing abilities will be affected if I notch. I have decided to play with a lighter and larger powerlift to see if this work better than the stainless steel setup I tried last time (CMC powerlift in stainless steel + stainless steel bracket = 170 lbs...).
Cheers and A Happy New Year from Norway!
Toffen