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Discussion Starter · #1 ·
I had a great experience working with Jack Foreman and wanted to share a bit to encourage those who might benefit from what he offers. Special thanks to Smackdaddy53 for pointing me in his direction.

My starting point was a flat-bottomed LT25 with a 20hp Mercury 4-stroke and a Stingray Jr on a jack plate, no tilt or trim tabs. Prop was a PowerTech SRT4R10P-TN15, I was getting 28mph with it at 6150 rpms. Once the top of the prop got close to the surface it would ventilate, had to back off rpms or height to hook up again. I fish a rocky area and was willing to trade some speed for better shallow water performance. I had 3" of jack plate that was not useful much above idle, my goal was to maximize the potential of my existing rig, not buy a new boat.

When I got in touch with Jack, the first thing he did was methodically walk through a list of questions to figure out what we had to work with and what the goal was. Basically, that paragraph above...

The Stingray Jr wasn't doing anything for me once it cleared the surface of the water. Having read the "TEXAS NON-Tunnel skiffs running Cavitation Plates" thread, I wanted to try a Tran Sport CP50 compression plate. Jack said to go ahead and do that and see where that put us.

The CP50 is a solid product. With black gelcoat it has a Darth Vader vibe. It looks really big on my little Mercury's lower unit, but Jack explained that for a flat bottomed boat, "this is your tunnel". When I did the install I removed the trim tab. Torque steer has not been an issue, the curved sides keep the lower unit aligned with the direction of the boat.

With the compression plate, top speed was one mph slower, 27mph, at 6200 rpms. I could run with the jack plate one inch higher than before. If I tried going up from there I could feel the bite become inconsistent and speed began to drop off. Nose of the boat was down, running much flatter.

Jack was happy with all that and said I just needed a prop with heavy cup. He does custom props for larger outboards, for the smaller ones he starts with a PowerTech and adds cup. Covid had the supply chain messed up, it was going to take a couple months to get a new prop to modify, so I sent him mine and had it back a few weeks later.

Testing was fun, Jack totally changed the personality of that prop, it was much better behaved. When it started ventilating before I had to back off throttle or height to lock up again, now I can just let it eat. Best speed is 27mph at 6100 with the motor an inch or so higher than before. When I run the jack plate all the way up speed drops to 25mph, water pressure is wimpy, and the boat starts to porpoise with so much of the compression plate out of the water, but those are all side effects of getting the height I was after.

I'm a satisfied customer, Jack was a pleasure to do business with. He knows his stuff and will save you a lot of trial and error. I got the prop I wanted and an education. Give him a call, his number is (361) 649-2789.

-- Carl
 

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Nice. Jack is great to work with, had him on my skiff once. I think people who have had issues with him in the past tried to insert their 2 cents. Like above, answer Jack's questions, tell him your goals and then STFU and let him do his thing.

So it will run at the height in the pic?
 

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"So how angry at shallow water are you?" That's how my conversation started with Jack. I told him what I have, what I want it to do. Check is in the mail sir.
He's a wizard well versed in the dark arts of propeller magic.
 

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Jack ain't going to work forever. I hope he's schooling someone to pass the torch to.
 

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Discussion Starter · #7 ·
So it will run at the height in the pic?
Yes, that's at the top of the jack plate. It will run 25mph there as long as I want, which is "not very long" at the moment, because the water pressure gauge is motionless on the zero stop!

Got out the laser level and tape measure. The anti-ventilation plate is five inches above the bottom of the hull. The skeg is a little less than six inches below the bottom. On plane it looks like about four inches from the surface of the water to the bottom of the hull. So ten inches to run, or call it a foot with margin? Limestone bottom = no cheating!

Next order of business is a low water pickup so I don't have to worry about water pressure.

It might run higher, but I'd need to move the jack plate to find out. I'm inclined to call it good for now.

-- Carl
 

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Yes, that's at the top of the jack plate. It will run 25mph there as long as I want, which is "not very long" at the moment, because the water pressure gauge is motionless on the zero stop!

Got out the laser level and tape measure. The anti-ventilation plate is five inches above the bottom of the hull. The skeg is a little less than six inches below the bottom. On plane it looks like about four inches from the surface of the water to the bottom of the hull. So ten inches to run, or call it a foot with margin? Limestone bottom = no cheating!

Next order of business is a low water pickup so I don't have to worry about water pressure.

It might run higher, but I'd need to move the jack plate to find out. I'm inclined to call it good for now.

-- Carl

I'm betting you are running shallower than that. Your hull on plane isn't drawing 4 inches of water. In fact when it gets rally sporty, your hull will rise a bit, signaling you to DON"T STOP NOW !
 
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Discussion Starter · #9 ·
I'm betting you are running shallower than that. Your hull on plane isn't drawing 4 inches of water. In fact when it gets rally sporty, your hull will rise a bit, signaling you to DON"T STOP NOW !
Lol, I've felt that in a guide's tunnel hull. Yeah, that's not a good place to stop!

I guessed at the planing depth based on the picture below. The water is about an inch above the outside corner of the hull, which is four inches above the bottom of the hull. I guess the water could be bumped up there by the boat's passage. What's a good way to measure the actual depth?

175711
 

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Discussion Starter · #10 ·
I'm guessing I could go higher by the fact that I can still get up on plane from the top of the jack plate.
 

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In fact when it gets rally sporty, your hull will rise a bit, signaling you to DON"T STOP NOW !
Yeah...when its shallow enough that the water is compressed between the bottom and your hull you can definitely feel yourself lift and start skating.

Worst thing you can do then is get spooked and back off the throttle...lol
 

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Thanks for the great info!
I’m in the same boat, literally :LOL:

I just got an LT25 with a 25 Tohatsu, & Bob’s Machine hydraulic jp.

Outboard has power trim & tilt

Only had the boat out once, but want to play with prop & cav plate

It has a 3 blade ss prop. It will break loose when lifted pretty early.
I feel it would do better with prop work & a cavitation plate.

I wouldn’t mind looking at low water pick-up also, just to be able to run shallow as possible

I appreciate the info you gave!
 

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Discussion Starter · #13 ·
Update... I added a transom-mounted low water pickup. Now I can run as long as I want at the top of the jack plate with no temperature issues.

-- Carl
 

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That’s so awesome!! Would love to see pics

I’m not real up on transom mount pickups.

Was it hard to add?
I know little about them, but if looks like they plumb into the lower unit by adding a pipe-barb?
 

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Discussion Starter · #15 · (Edited)
Note: pictures removed at Smackdaddy53's request.

I followed Smackdaddy53's design in post #10 of this thread. I was looking for a project to practice tig welding aluminum so it checked a couple boxes for me.

I drilled and tapped the wash outlet on the lower unit for a 1/4" npt elbow to 1/2" hose barb fitting.

I was running out of water pressure on the top 1-1/2" of the jack plate. I was originally planning to block off the top of the side pickups, but it works fine without that, no check valve or anything, running both supplies in parallel.

-- Carl
 

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Wow you did a great job, super clean install!!

Love the strainer mount too.

Your aluminum tig work looks great to me!!
That’s on my future learn list. I’ve migged & tigged for many years, but only steel.

You have really inspired me for my LT25.
Going to start with the CP50, and follow with low water p/u & prop

I really appreciate you taking time to post your progress Carl!

Dan
 

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Discussion Starter · #18 ·
This is why Mac didn’t want to post photographs of his work until the patent process was complete.
I like Mac's setup and corresponded with him for a couple months trying to work out a path to getting one installed. The drive from Central Florida to his shop in Texas was a bit far, and he wasn't yet ready to have anyone else do an install. I didn't set out to make my own but I needed a solution... because there are snook that need catching!

-- Carl
 

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Pictures below...

I followed Smackdaddy53's design in post #10 of this thread. I was looking for a project to practice tig welding aluminum so it checked a couple boxes for me. You can see that I still need more practice! 🙂

I drilled and tapped the wash outlet on the lower unit for a 1/4" npt elbow to 1/2" hose barb fitting.

I was running out of water pressure on the top 1-1/2" of the jack plate. I was originally planning to block off the top of the side pickups, but it works fine without that, no check valve or anything, running both supplies in parallel.

-- Carl

View attachment 178085 View attachment 178086 View attachment 178087 View attachment 178088
As flattered as I am I need you to remove these photos please. I have several years, over $20k invested and a patent in progress for my pickup system. You really should have reached out to me before posting these photos.
I’m coming to Florida for about a week to pick up a Chittum and do a couple of installs while I’m over there, I could have gotten you in if you were patient.
 

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I have to say, Mac’s being decent about this. He put a lot of time and money into this, and he was reluctant to post photos here. Many asked for photos, wanting to understand if his idea was truly revolutionary, or just more wishful thinking.. He finally gave in, trusting (perhaps naively, but trusting just the same) that the folks here would respect his endeavors. I offered to front him some money at no interest to start production; repay it whenever, and he refused. I know he would honor the loan, and he was anxious to move faster, but he wanted this to be entirely HIS invention, and he didn’t want to feel beholden to anyone. I respect that; I am much the same way.

The point is, by plagiarizing his work you violated that trust, and you showed very poor judgement. A lot of other people wanted his pickup besides you, and some had the money but had to wait for supply. Others had to wait until they could afford it. Many are still waiting. But stealing a man’s ideas and work is not cool. Pull the pics. It’s the right thing to do…..
 
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