# Flats Cat versus everybody else...



## chofujohn

Hi Guys,

I've already read all the posts relating to flats cat boats. There is one that was left out of the discussion and it's the Dream Boats Intruder in both 21' and 18'. The owner of the FL based company even took one to Bermuda and on to Europe. Is it possible there is one boat that can do it all? I have doubts.

So, the real reason for this post is to get the straight skinny on engine cooling issues while running shallow. I've been to the www.flatscat.com website so many times that I have their specs practically memorized. But, what entices me most is their patented hull that directs water up into the tunnel and thereby keeps cooling water flowing to the engine. I'd like to know how the cooling issues are solved in competitor hulls. I've read enough about overheating engines that I've become wary as I shop. There may be boats out there with better fit and finish, but that's less of a concern to me than the engineering. Is there another flats boat besides Flats Cat that will run with the prop even with or above the bottom of the hull? If not then it would appear Flats Cat is the king of the flats. They also have five pages of testimonials that are mighty convincing, too. Again, I'm interested in knowing how cooling has been solved in non-Flats Cat hulls.

Best Regards,

John


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## patwilson

Welcome aboard....


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## CaptDocHoliday

There are several Transport and Shallow sport models that run fine with the prop even with the bottom of the hull. My 14.5 Shoalwater will do it too at the right speed and with a cavitation plate. Flatscats are a good design, but not necessarily "the ultimate" design. That is and will always be in the eye of the beholder. Low water intake on the lower unit will also buy you several inches of motor lift you wouldn't otherwise be able to get.


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## bayskout

21 rfl or curlew

& consider the hole shot


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## Fishspert

Many manufacturers have sales pitches and gimmicks that sell boats. On flats cats website under the performance portion they claim that the hull "compresses", and "compacts" the water. I hate to tell you this but that is not possible, however can be redirected in a way that would allow the boat to run the way it does.

Boats are all about compromise and trade offs, no one boat does it all and does it all well.

I am not saying this is a bad boat, but what they say on the website is just talk. 
Best way to quantify what a hull does is to get out and run it.


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## CaptDocHoliday

Hulls such as these will also be very noisey (hull slap). That is the one thing I hate about my Shoalwater. Solution is to troll with the wind when possible.


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## cruss

*water*

Just put a low water pick up on your lower unit and it doesn't matter.


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## Friendswoodmatt

I had an FC-- yes it will run with the prop above the bottom of the hull, but it will not go nor will it get up where an RFL will. As far as cooling issues--you need to talk to a guy on here named Railbird. He can give you the skinny on being cool while runnin really really skinny


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## Flat's Hunter

Flats cat has a good marketing gimmick, but that is about it, it may help some.Not a bad boat, but I think some of the cats are a lot better, buts that's my opinion. Dream work boats was discussed on here awhile back. There boats look like most cats, nothing that's looks special but I have not seen it in person. If I remember the builder kind of made an *** out of himself trying to say how great his boat was


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## railbird

The easy answer is the flats cat will run very shallow. If operate propperly it will go just about anywhere, except places where only the rfl will go. If you want the shallowest running boat on the market, go get an rfl. 

I can run extremely shallow with the skeg completely above the line off the hull. The shallower you run, the less force you need to move foreward, therefore my setup and can run with the trim all the way into tilt and it will still be on plane. Many if not all cats can cover 4" of water with the skeg above the hull line. No boat can do it at WOT for long periods of time without overheating. 

Just remember the turtle always wins the race on super shallow areas. The slower you go the less water you need to cool your engine and the more water your tunnel or cat hull can collect to feed the waterpump. Also when you screw up its usually not as bad because you are going slow.


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## RedXCross

I had one for 3 years as my flats hull, pretty much what is mentioned above, if you feel like you want more info. PM me or one of the other owners. I ran a Suzy on it, it was dependable. Just like Chuck said RFL. SHALLOW.


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## specks&ducks

Doc Holiday is right on the hull slap. I have noticed this a couple times while being around them while they were at anchor. Maybe this is splitting hairs but your going to be taking that thing into some really shallow quiet areas to fish so it should be on a list of things to consider. I do think they are good boats though, but like many have said, all boats have a trade off. Just go run them and find one that fits you best.


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## kenny

specks&ducks said:


> Doc Holiday is right on the hull slap. I have noticed this a couple times while being around them while they were at anchor. Maybe this is splitting hairs but your going to be taking that thing into some really shallow quiet areas to fish so it should be on a list of things to consider. I do think they are good boats though, but like many have said, all boats have a trade off. Just go run them and find one that fits you best.


Flatscat is not a technical poling skiff. It's a flats boat to get you where you want to wade. They drift fine and I never noticed hull slap kept me from catching fish, but I usually cast some distance from the boat. LOL

I also think, on the upper coast, the ability to run shallow and get up shallow is waaay over rated!


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## Totally Tuna

Fishspert said:


> Many manufacturers have sales pitches and gimmicks that sell boats. On flats cats website under the performance portion they claim that the hull "compresses", and "compacts" the water. I hate to tell you this but that is not possible,
> 
> Fishpert is on the money here. You cannot compress H2O. That's why you have an air compressor, but a water pump. Water at 1000 psi will have the same volume as water in an open bucket. I hate advertisements that make claims like this. Reminds me of the way Democrats run election campaigns.


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## chofujohn

*Thanks for the welcome, Pat.*



patwilson said:


> Welcome aboard....


I've been reading here for some time, but a lot of the stuff relates more to Tejas Gulf coast versus Florida. I'm a full-time motor home living fisherman and at my age I've decided to make up for lost time and try to get as much living (fishing) in as possible. Being retired gives me the freedom to do what I please. Sorry, I made a mistake. Let's start over. Being divorced gives me the freedom to do what I please and what I've figured out to this point is I need a boat that will do inside and outside. That's why I found the articles and videos about Dream Boats to be so interesting. Those brothers took their 21' cat flats boat and crossed the Atlantic with it. They dodged icebergs and fought through 15' swells and confused seas. It's amazing they survived. The website is www.dreamboats.net. Like the rest they are claiming the ultimate design.

Later,

John


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## Flat's Hunter

chofujohn said:


> It's amazing they survived


That pretty much the point. Another way to say it is they are lucky they are alive. Quite a few boats can survive, the point is its not smart to cross the Atlantic in a small flats boats. It's just another gimmick.

This is a place of Texas fisherman, so that's what you will see discussed.

Not saying dreamboats is bad, it's just another boat here in Texas. If you want a big bad cat try dargel 24' kat. Not as shallow as a flats cat but a much more open water boat. If you want a true offshore cat that can be shallow as 6" try shallow sport 27 latitude.

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## BBKing

It is true that you cannot compress water, at least not at the pressures we're talking about. However, you can compress the air that is mixed with the water in the tunnel. I would think this makes the water less turbulent and results in better efficiency for the prop as well as for cooling.


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## kenny

Totally Tuna said:


> Fishspert said:
> 
> 
> 
> Many manufacturers have sales pitches and gimmicks that sell boats. On flats cats website under the performance portion they claim that the hull "compresses", and "compacts" the water. I hate to tell you this but that is not possible,
> 
> Fishpert is on the money here. You cannot compress H2O. That's why you have an air compressor, but a water pump. Water at 1000 psi will have the same volume as water in an open bucket. I hate advertisements that make claims like this. Reminds me of the way Democrats run election campaigns.
> 
> 
> 
> Yeah, other boat manufacturers NEVER make unsubstantiated claims about their products performance! :spineyes:
Click to expand...


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## chofujohn

*I'm reading your replies with great interest...*

Nobody has yet offered a technical explanation as to how the Flats Cat's competition is able to ensure adequate cooling water to the lower end. One of the replies here stated that none of the current crop of shallow running cats can sufficiently cool their engines running WOT while jacked up and running skinny. I believe that is one of the attributes of the Flats Cat.

I called Dream Boats yesterday and spoke at length with the owner, Ralph. He seems like a nice enough guy, but he wasn't very interested in selling me a boat. They have made and sold 32 to date and his interest has actually shifted from making flats boats to a new project he's promoting. He's trying to raise the money for a prototype 78 foot power cat that will utilize his proprietary hull design. He's trying to reinvent the mega cat by making it run more economically. He believes he will own that market eventually. I wish him luck and only time will tell. Volumes have been written about unrewarded genius and I'm not saying he's that smart. What Ralph has is tenacity and courage. Something I'm not sure he's considering, though, is that the super rich who can afford jillion dollar yachts can also afford the diesel required by their engines. Again, time will tell. When I asked about his flats hull and how it feeds cooling water to the lower end he told me he "directs" turbulent water into his tunnel by way of multiple critical angles in the hull. His explanation wasn't scientific, but I couldn't hold that against him and I didn't press him. What concerned me was the water he's directing is highly aerated and not as dense as the solid column of water that fills the Flats Cat tunnel. He also talks about how air is compressed to "lift" the hull. That's where I lost interest. Enough about Dream Boats. The only reason I've brought up this subject is because I have enough to worry about without adding the stress of wondering if my engine is being adequately cooled. No sense shortening the life of an engine if I don't have to.

I'm currently thinking that Flats Cat has the best engineered hull. But, until my money is plunked down on the table I'm open to suggestions. I accept that Flats Cats are not as fast on the same HP and that they might run rougher into straight on waves, but that's not the real name of the game, right? Like one of the replies pointed out all boats are a compromise and I couldn't agree more. The same is true of airplanes as well, btw. So, I guess all we can do is add up the pros and cons and make as informed a decision as possible. With your help that is my hope.

Btw, the 21' Intruder from Dream Boats is $23k bare and nicely equipped at $40k. He's not a Mercury dealer, so a Verado would have to be found elsewhere. I guess that's what the Internet is all about, eh?

Thanks,

John


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## rojogrande

Curlew by far and you have a semi V on it.

With a flatscat make sure you have a good chiropractor on staff


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## CaptDocHoliday

Dude, you need to go ride on some other boats. I think your understanding of tunnel hydrodynamics is flawed based on stuff you have seen on YouTube and not real world experiences. Not trying to be a Richard here, but google will only get you so far before you need to actually test several different models.


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## Flat's Hunter

x2 in that. A few years ago I thought the flats cat website was the end all be of tunnel hull boats, then I saw all the others. All the other tunnel hulls work about the same, the flats cat tunnel doesn't make that much of a noticeably difference, if any at all. I have seen flats cat get stuck just like any other boats. If there are differences between the cats your talking an inch or so, meaning the boats ability depends a lot more on the drivers ability to operate it. It is a skill to drive a boat through the shallows. Railbird above is one of the masters. He can take his 21 majek redfish line with a Honda outboard and literally go through puddles of water. I mean literally big puddles, I and many others have seen it. If you saw what his "normal" but efficient tunnel could do you'd be amazed. Looking at it you'd would be justified at saying railbird was a dam liar for saying he could run through that, it looks impossible, but you have to see to Believe. 
Point being- you don't need that fancy inverted angle compressing tunnel to be able to run shallow. Sure some tunnels are better at holding water than others, but all of them work the same, they just don't have a website full of neat little graphics. if they were somehow superior, you would see them dominate the market, which I don't see. Tran, Shoalwater and Hanie sell a lot more boats


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## Greg E

Good point. There are so many shallow running boats. I would buy a boat more on what style of fishing I did. I run an 18 ft shallow sport classic. We normally Wade so the flush deck and low profile are perfect for me. And it runs very shallow with very few overheating issues.


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## devil1824

rojogrande said:


> Curlew by far and you have a semi V on it.
> 
> With a flatscat make sure you have a good chiropractor on staff


You have got to be kidding me. I have ridden in and driven a flats cat plenty. You don't get much smoother then a cat. It rides better then my bass boat.


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## ATE_UP_FISHERMAN

I've owned one since 2004 and have to say I've never had a problem getting stuck anywhere. I dont want to start an argument but i will say of all the flats boats the FC tunnel holds water better than any. I think the reverse angle in the tunnel has a lot do do with it. I run a Yamaha 4 stroke without a nose cone intake and can jack the motor up all the way and never worry about water pressure issues. The only issues I have are with the speed. You will see low 30s in most cases.


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## Redfishr

As mentioned......At your age I would also concern myself with the ride.
I'm not that far behind you and I cant stand being pouned ANYMORE on boat rides, and wont be.
There are too many good riding boats that run skinny to have to be beat up.
There is NO WAY I would buy a Flats Cat or an RFL.
If you have the freedom of NO job then get to some dealers and test drive some boats day in and day out.
There is no reason to buy the wrong boat in your case, you have the time.
Believe me, if you buy the wrong boat, you'll know it pretty quick.


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## rojogrande

devil1824 said:


> You have got to be kidding me. I have ridden in and driven a flats cat plenty. You don't get much smoother then a cat. It rides better then my bass boat.


Not sure how a FLAT bottom cat hull could ride better than a bass boat...:bounce:


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## billclemens

chofujohn said:


> I've been reading here for some time, but a lot of the stuff relates more to Tejas Gulf coast versus Florida. I'm a full-time motor home living fisherman and at my age I've decided to make up for lost time and try to get as much living (fishing) in as possible. Being retired gives me the freedom to do what I please. Sorry, I made a mistake. Let's start over. Being divorced gives me the freedom to do what I please and what I've figured out to this point is I need a boat that will do inside and outside. That's why I found the articles and videos about Dream Boats to be so interesting. Those brothers took their 21' cat flats boat and crossed the Atlantic with it. They dodged icebergs and fought through 15' swells and confused seas. It's amazing they survived. The website is www.dreamboats.net. Like the rest they are claiming the ultimate design.
> 
> Later,
> 
> John


The crossing is pretty impressive.


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## yakfinaddict

chofujohn, 
The Flats Cat is a great boat if you want a little bit of everything in a boat. From what you are saying it seems that you want to go shallow more than deep so the FC is good. I have a buddy who has had one for years and we take it everywhere the RFL, Shallow Sport, Shoalwater, and many other "flats" boats will go. Like someone else said it depends on the driver. I've seen some idiots with $50K boats and they don't know how to drive, next thing you know they stick it in mud that you can't walk in. 
The hull slap some have mentioned is going to happen on most, if not all, flats boats, I don't care where or how you drive, some hull slap is going to happen (unless it's like glass).
The tunnel on the FC like someone else said does not compress the water but directs a column of water to the lower unit giving it the capability of running with the prop at, or above, hull level. The only way to prevent overheating is to always have a good supply of water going to the intake because "if you aint *******, you're going to be ******". Like one of the guys mentioned, when your shallow you can run slow and easy if you know how to drive. I've been looking for a good all around boat for a while now (3 yrs.) but haven't found one that can do "absolutely" everything. Crossing the Atlantic is not on my to do list but knowing that a boat can handle that is a feat among itself. 
With all of this said I hope you find what your looking for! There are a lot of choices out there and the picking can be daunting but the FC is a good choice for shallow water adventures.....as long as you can drive!!!


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## railbird

I will attempt to explain how all hulls (tunnel or cat hulls), deliver water through the tunnel to cool the engine. Its called the "ventury effect" its a process where water is pulled into the tunnel as water is forced out the back by the prop. Water has a refractive property which can pull other water molecules in the same direction of thrust. An example of refraction, take a pencil and hold it at a 45 degree angle and pour a small stream of water down the pencil and watch as the water runs down the pencil it will create a stream of water down the pencil. If it wasn't refracting to the pencil it would fall straight off of it, because it tends to refract water redirects down the pencil. I used this trick to put oil in my hydrolic steering when i didn't have a funnel.

Venturi's have been used for years in many places, such as the mesquito foggers that were used in the 60's and early 70's. Remember the fogger you had to pump the handle and it would pull chemical into the orphice to mix with the air traveling over the dip tube in the chemical. The fogger uses air to lift the chemical by passing it at a high velocity over the top of the dip tube, the velocity of the air creates a vaccum on the tube lifting the chemical. 

The tunnel works much like the pump sprayer in that as water is rejected from the tunnel by the prop it pulls all water molecules under the tunnel to the location where water is being forced out the back of the boat. 

Now for why no boat including the flats cat can't run WOT across 3" of water. Part of what allows the tunnel to feed the motor water for cooling and thrust is what someone referred to as the doppler effect. (Next time you are in the pool or in the bathtube, use your hand and quickly force your hand downward. The water that shoots up in the air is caused by the doppler effect.) It goes something like this, when a boat travels along the surface of the water, it displaces water (lets say we are running down a deep channel), on my boat it might be 6" or so. When that water is released from the back of the hull, it rebounds upward. This rebound is equal to the depth the hull is displacing water as it is traveling down the channel. This is why the river of water leaving the tunnel rises up as it leaves it. This rebound is the very reason engines can run with the prop above the bottom line of the hull.

I may be rambling here a bit, so i will try to pull it together. The reason a flats boat can't run WOT over super shallow water is there is less displacement of water in 3" on the flats because the hull tends to rise up and run higher in the water. Water is trapped between the bottom of the boat and forced through the tunnel, kind of like hydroplaning in a car on wet streets. In a channel water is displaced and moved downward, on the flats, water that would be displaced downward, can't because it hits the bottom and is trapped by the hull. If the boat is moving fast enough to move past the water under the boat before it can escape from under it (to the sides), the boat stays on plane. A boat in the channel will have 6" of doppler effect and a boat on a 3" flat can only have a 3" doppler effect. When you add the speed of WOT there is not enough time or water to feed the engine for cooling. WOT on a 3" flat will blow out the tunnel and overheat the engine. Remember there is only about 1/2-2" of water under the hull when running in 3" of water meaing there is less water available to the tunnel, when running super shallow. 

When i find myself in a super shallow situation, I slow down and try to cruise. This works the engine less requiring less cooling and allows the tunnel time to deliver the water. I'm too hungover to study this so if any corrections are required someone please chime in. This is how i remember it was explained to me.


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## bowhunter63

*Dreamboats*

Seen and fished out of the 18 nothing to be impressed by had a flatscat boat that would do just as good just looked at a bonefish that was very impessive dreamboat was to much salesman bull


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## BBKing

Railbird, I can't honestly say that I understood much of what you wrote; you're way over my head. However, there is one factor that I don't think you refer to which seems to me to be very important and that is the vacuum created within the tunnel that in effect sucks water up and into the tunnel. Also, I don't think that a true catamaran creates this vacuum and must rely only on the boats wake as a source of water to the tunnel. If my comments are correct then not only will a flat bottom mono hull, like the Majek, draft shallower than a Cat but it should be able run shallower and provide more water to the tunnel. I'll go back and read your message and see if I can put it in terms that my simple mind can understand.


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## railbird

BBKing said:


> Railbird, I can't honestly say that I understood much of what you wrote; you're way over my head. However, there is one factor that I don't think you refer to which seems to me to be very important and that is the vacuum created within the tunnel that in effect sucks water up and into the tunnel. Also, I don't think that a true catamaran creates this vacuum and must rely only on the boats wake as a source of water to the tunnel. If my comments are correct then not only will a flat bottom mono hull, like the Majek, draft shallower than a Cat but it should be able run shallower and provide more water to the tunnel. I'll go back and read your message and see if I can put it in terms that my simple mind can understand.


I totally agree with you that a monohull like the rfl and others will run shallower than a cat hull. The problem is we are talking about a difference of maybe a few inches.


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## cpthook

I also think, on the upper coast, the ability to run shallow and get up shallow is waaay over rated![/QUOTE]

Agreed on upper coast, its a waist on galveston bay, but essential down south.


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## Run-skinny

There are several boats mentioned in this thread that can run in shallow water. Try out these boats and see what you like. We are bringing in Flats Cat to Corpus. These boats will be rigged with a jack plate, and an E-TEC Evinrude outboard. The first Flats Cat hull will arrive this Saturday (March 24th) at our dealership. We plan having a 17 footer and a 21 footer arrive around noon at our Grand Opening. The boat will not be rigged at this time, but will be rigged over the next week or two. Feel free to come by and take a look at the hull during our grand opening. Once it is rigged and ready to go, you are welcome to come by for a test drive.
B & S Watercraft and Marine
1109 Cline Street


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## devil1824

That's great news! Now all he needs to do is to add some different color options. I'm a big fan of flats cat, hope it works out!


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## redman35

Don't forget about the illusion for skinny


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## [email protected]

Here's an idea, buy a semi "V" enjoy the ride and wade or kayak into the shallows where you should be fishing and not running your boat anyway! 

Ooops! Did I just post that?


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## devil1824

[email protected] said:


> Here's an idea, buy a semi "V" enjoy the ride and wade or kayak into the shallows where you should be fishing and not running your boat anyway!
> 
> Ooops! Did I just post that?


Typical snob yakker. sad4sm


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## wadehedtke

Whats in the rumor mill regarding the new Phantom that Mosca is putting out? Looking at one tomorrow so I'm appreciating all yalls input.


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## ngrow

railbird said:


> I totally agree with you that a monohull like the rfl and others will run shallower than a cat hull. The problem is we are talking about a difference of maybe a few inches.


Off topic.... But when comparing the RFL and motors, how does the TRP compare to a single prop? (in terms of getting on plane and running super shallow)


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## ATE_UP_FISHERMAN

You need to go by and check out the Flatscat operation in Rosenberg.


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## ATE_UP_FISHERMAN

ngrow said:


> Off topic.... But when comparing the RFL and motors, how does the TRP compare to a single prop? (in terms of getting on plane and running super shallow)


It's like comparing a 2 wheel drive truck to a 4 wheel drive.


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## InfamousJ

that's a funny ad picture.. dry land mud flying.. LOL... time for a 501 airboat


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## [email protected]

devil1824 said:


> Typical snob yakker. sad4sm


D - You don't know me! I do all kinds of fishing!!! I am allot of things but a SNOB I am not.


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## bayourat

InfamousJ said:


> that's a funny ad picture.. dry land mud flying.. LOL... time for a 501 airboat


I love the hills in the background.


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## bait buckit

What's funny is the smoothest an driest on there advertisment. I've been in my share of cat boats an haven't seen any that are that blowing across the bay


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## ATE_UP_FISHERMAN

Look at the dargel 25 Kat


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## kenny

bayourat said:


> I love the hills in the background.


Flat Cat, preferred by 9 out of 10 drug smugglers in Big bend!:wink:


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## M.Taylor

Tran cats are better...but I'm just being biased as hell!!! Lol. I know, we should all bring our boats to the same flat...and see how makes it further!!! Some body's probably not coming back!!! LOL!!! Everyone just stop trying to figure out which boat runs shallower and go fishing, if you ain't got a boat...buy one from Donny


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## Run-skinny

*Flats cats have arrived in corpus*

If you would like to check out a Flats Cat for yourself, they are here in corpus. You do not have to drive to Houston, we have the Flats Cat at B & S Watercraft and Marine at 1109 Cline street in Flour Bluff. Come by and check them out.


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