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Pro's & Con's between full tunnels and tunnels with center pods

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Old 11-16-2003, 08:34 PM
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Default Pro's & Con's between full tunnels and tunnels with center pods

I have a twin engine 30 foot cobra tunnel, but thinking about down sizing to a 26' to 28' tunnel single engine. I really like the looks of the Commander 28' and the Elite 28' tunnel's. I also like the 27' levey craft saber 257carrera effect.and the 27' cougar. I beleve these boats have a center pod. I know that a center pod can help in making a more comfortable cabin and crawl through bow rider, but how does it effect handling. My wife wants something with more room and I still want performance and looks but would like to go back to a single engine boat but still want to play with tunnels. what are the difference's performance wise between full tunnel and tunnels with a center pad

Last edited by Two K's; 11-16-2003 at 09:02 PM.
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Old 11-16-2003, 09:38 PM
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wow, this question is just about as difficult and as controversial as the difference between stepped hulls and conventional Vs. I will just say that in theory, a center pod will handle heavy seas better while the ones without should in theory be faster, especially on flat water. In practice however, it's not that easy. Peters and Hledin have been designing their cats the way they do for a long time. I know that Buzzi thinks that a cat with a center pod is bound to be a poor-performing hull. But then Gary Armington of Talon has designed a fantastic hull which is now being used by Hustler to build their popular 377. And that boat held the kilo record for quite some time so it is fast, no doubt about that. So it's again one of those cases where everyone has their little recipe but there may be more than one good solution to the problem of designing a good tunnel hull. And other design features may be more important than the presence or absence of a center pod. My advice is: test all of those boats you mentioned and make your mind up based on that not on rigid criteria like the presence or absence of a specific design feature. I also strongly suggest that you look at the Talon 25. It's basically a smaller version of a 377 and I am told that it has very similar dynamic behaviour. I rode in a 377 several times and it's quite something. It leans into turns like a V bottom and has none of that tramlining, pushing you to the outside feel of some other cats. I think Talon is still making the 25 exclusively for Lake Cumberland dealership but not sure though.
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Old 11-17-2003, 08:15 AM
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Theres one more question you leave out of the equasion super t. Does the pod finnish above the sponsons or is the pod like a full depth center sponson. ie,the difference between an 25 eliminator daytona and a 25 talon. Both ride very differenty form one another.
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Old 11-17-2003, 08:53 AM
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"I will just say that in theory, a center pod will handle heavy seas better while the ones without should in theory be faster, especially on flat water." ST

Wow, I've always been under the assumtion that it was the other way around. Please explain the rational. Seems to me the pod just creates more of a 'flatter' and shallower tunnel that will tend be harsh in big water.


Two K's,
Why are you thinking smaller? What are your feelings about the Cobra? How does it handle the rougher waters around NY? How do you think a smaller cat will handle the Sound? Many of the boats you've mentioned are better suited as lake boats and I think your wife may strongly frown after she gets the crap beat out of her in 3'-4' chop.
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Old 11-17-2003, 09:45 AM
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I know that if the pod is deeper than the outer sponsons that the boat will turn flat, if not lean in just a tad.

The 26' and under cats generally do not have any cabin space. The two exceptions are the HTM (24') and the Awsome (26').
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Old 11-17-2003, 07:22 PM
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Thanks for input guys. SS930, the main reason why I want to go smaller is I want a single engine boat. The other reasons are my cobra fits 5 people in it and the others fit 6 I have only been out on the boat 4 times and each time the kids argue whos friend will be comming with us. And my last reason which shouldnt count really as a reason is I can't get the boat out of my driveway without asking my neighbors to move their cars. I can drive it across the lawn which is what I have been doing but the tandem wheels are ripping up the lawn. But I can find a place to store it during the summer I just thought I would look around. As for the cobra I like the boat alot I have only driven it about 5 times It's my first tunnel and the only one I have ever driven or rode in It handles really nice and it felt safe. I still have some finishing work to do to it like trim indicators for the drives and installing a hatch lift. I am still playing with props to get it to plane faster but once its on plane it goes like hell. I only got it in the water at the end of september and I'm still at the learning stage but feel very comfortabe with it except around the docks.It seems to handle rough water very well and I don,t get wet from spray I love the way it looks and Im just kind of looking around while I'm playing with this one But a couple of feet smaller and having a 6 seater would help and I thought a center pad would give me a walkway into a small cabin area for a head and bunk The commander looks alot like the cobra and so does levey crafts sabre thats why I was asking about them Sorry for long post and thanks again for any info

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Old 11-17-2003, 07:46 PM
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If you are looking for cabin space, the HTM has the biggest cabin in that size range. The awesome 26 has a good size one also as said above. The 26 eliminator has a small cabin also. The HTM is a good combo as far as speed and cabin space is concerned. They are priced well also. With that being said, I would question how good these boats will run in your area compared to your 30 foot cobra. I also thought that the true tunnels ie Skater, Motion, Spectre were better rough water boats.
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Old 11-17-2003, 08:15 PM
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A center pod is a must for the ultimate storage and keeping your BEER COLD,just pack it in and dump lotsa ice on it and you'll be set AS for your driveway delimmla,don't you know the guy down the block with the bulldozer that moves houses? Oh yeah, i got those indicator pieces you were looking for and another cable outa the poorold magnum that met the sawsal Tripps
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Old 11-18-2003, 07:40 AM
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SS930, in theory the absence of a center pod leaves a flat tunnel surface which is in theory better for obtaining an air cushion and an undisturbed air flow in the tunnel. Such hulls should ride slightly higher and thus faster. Think about Formula 1 racing. Flat bottoms produced a strong venturi effect which glued cars to the track due to a virtually undisturbed air flow. In order to reduce performance by reducing this effect, the authorities imposed the presence of a middle section, a board which disturbs this flat surface. The underbody aerodynamics were disturbed, the venturi effect reduced as well as speeds in turns. A center pod has the same effect: it disturbs the underbody aerodynamics by upseting the air flow.

Airpacker, I am not familiar with those boats but the difference you're talking about is a difference between a catamaran and a trimaran or a 3-point. I was assuming 2Ks was talking about cats only. And Cord, leaning into turns depends on other design features than just the center pod. The Talon leans into turns yet its center pod is way shallower than side ones. I guess you are right but it is not a sine qua non condition for leaning into turns.
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Old 11-18-2003, 07:53 AM
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I think you'r mixing theories. THe Formula 1 cars have the venturi effect and low pressure and stick where the cats are packing air and creating lift in a upward lifting wing effect. The center pod makes a big difference where it ends- that is, is it even with the sponsons or is it raised. If it is raised above the sponsons - stopped it will provide more boyancy and keep the stern up, at mid speed it will be in the water or just touching the water and it will define the level of water going to the prop, At high speed it will be out of the water and not cause any additional drag and will help to slightly reduce the tunnel end opening size and therefor cause greater packing of air and greater lift. It seems to work/layout better in the smaller cats and the larger 32'+ cats have bigger sponsons for boyancy and the sponsons are used to define the level of water to the props.
Where's the engineers on this one?
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