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Motor height

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Bought a 24' bay stealth recently. Ran it for first time a few months ago. Topped out at 53mph.
Then I put on an 8' manual jack plate. Installed it all the way lowered. Lost some mph. Went down to about 47mph
So I jacked it all the way up. Ran it and lost more! Tops out at about 43mph now.
Is it too high? Feels like when turning it doesn't catch the water. I attached a pic to show the water line while running about 75% throttle.
The prop shaft seems to be even with the bottom of the hull.

Any help or opinions is appreciated.
Thanks!
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Not always plug and play
' Every action has an opposite reaction' , I think it was Enstein said that , I do know from when I put a manual jack plate on my old refurbbed 1978 Mako 20 w/140 , it wasn't no where near 'Plug and Play ' , it took a lot of tweeking , at times I was thinking I made a mistake , I must have move it up and down 40 times , put wedge shims in and out , I ran at least 10 different props and found the one with the best bite and least cavatation in turns was a 4 blade which was reworked with extra cup and the hub was drilled for extra exhaust to help get on plane from what I was told , also ran an Edge anti-cavatation plate over the top the prop which was a must running tight winding bayous as it would cav out ----- I should have never sold that boat , it was a fine running , dry boat in rough water , it would only run right at 45 mph and running down Terra Beouf to Black Bay in the morning all the bigger Well Crafts , Aqua Sports , Grady Whites would pass me by running 50-55 mph , when we hit Stone Island on the way to Battledore I was passing them ----- that boat rode well with out a jack plate , once it was tweeked out it rode great
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Height
So you did find the sweat spot? We\'re you able to have the motor higher and also gain mph?
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sweet spot
To answer your question : Did I find the sweet spot ? .... yes , but not without doing other modifications , I would say the jack plate alone, over all , hurt more than helped , I was very disappointed with it right off the bat , and it cost a lot of test runs and money to get it right, I borrowed so many props and never did really find the right one , got one close and then bought one and had it custom tuned ------ I would go one way and improved some things and hurt others and going the other way and caused other problems ..... I remember going down with it and having more control in turns but lost speed and threw rooster tails off both side the cav plate straight up behind the transom , went up too high and had no control in turns and it would cavatate bad and I could lose it in a tight bayou and spin out .... after finding the right prop , hydraulic trim tabs and a cav plate it ran like another boat ------ I don't remember the exact numbers on speed but it wasn't a lot ,around 5 mph max , the boat was heavy fiberglass vee , what I really liked about it after it was all set up with the jack plate , trim tabs , prop and cav plate wasn't speed , but a much better ride in rough water , the ability to run at a much slower RPM and stay on plane , the ability to jump up on plane without going thru the extreme bow rise thing , which helped getting up in swallow water ------- I think the design of the hull has a lot to do with the results you would get , some boats might be plug and play , others ain't so easy I know cause I went thru it
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kickstart
all I know is I was told cav plate even with bottom of boat?
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'Spirals of Upgrading'
Geronimo sez... 'Should Have Left Good Enough Alone'...cheers
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admiral
like they say if it aint broke don't fix it!!! I agree!!! 53mph I would have been happy as heck?
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Reason installed
Oh boy. I hope I don't have to go through the same issues.
The bay stealth has a recessed motor. In order for me to put the power pole on without drilling into boat I had to get a couple motor plates. One was almost as expensive as the jack plate. So I just got the jack plate and mount that hooks power pole to it. As you can see from pics.
I assumed the jack plate would only help. :/
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kick
picture not to good u got it running back at 53mph????
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can of worms
...the cavatation plate is at the bottom of a boat without a jack plate ...... but.....when you use a jack plate or a Gill bracket , Armstrong bracket (transom extension) it isn't the same , you go so much up for so much back , all types of hulls have different reactions , and the prop makes a difference ..... I have seen boats 5 inches up on a 6 inch plate , and others 2 inches up on a 12' , so there is really no rhyme for reason , on boats with transom extensions a boat that is a long shaft 25 inch will run a short shaft 20' --------- can anyone say ' opened up a can of worms '
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Worried
I am optimistic. I'm hoping that a few more inches lower and I can have her running in the 50's again.
I will for sure repost back next test run.
Hopefully accompanied with a good fishing report!
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kickstart?
I would think you would be burning more fuel also? not sure? good luck hope you get it right!!!
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mpg
I think once he gets it all tuned in , the mpg and mph will be better as drag will decrease as the geometry of the hull is improved , I think a prop change is going to have to happen to get the max out of it and keep it at the recommended max rpm's ------- the biggest kick for the buck for improvement I think would be a anti-cav plate , the Edge is my choice
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motor
I put a 6' manual jackplate on my 18 ft all. bay boat. the motor is with the cav. plate aprox 1' above the bottom of the boat. I got a better ride and a small increase in top end,but I hardly run my 115 yami 4 stroke wide open mostly around 4000 rpms. What I noticed the most is a better ride. I also have a 14 ft flat with a 40 hp yami with a 4' jackplate this is also raised so I can go in real skinny water, it also has pods no real increase in speed either.
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jackets??????
don't think these jackets will help his motor height???
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