Originally Posted by SS930 (Post 3611868)

Old news! :D

http://www.offshoreonly.com/forums/g...-optional.html







+1 Steve!

Originally Posted by pstorti (Post 3611911)

doesn't really seem like a good solution to me, seems like a half ass way of doing it. The boat and tunnel are probably designed for a pod and I would guess it will have issues without it. Secondly unless the tunnel is made deeper just eliminating the pod doesn't make it ready for offshore. But what do i know. Step in the right direction though!

Originally Posted by Matt Trulio (Post 3611874)

Unless you want to read a direct quote from Dave Hemmingson, you're right. :)

Originally Posted by RiverDave (Post 3612107)

You are thinking of this in a traditional tooling sense. With 5th axis CNC you can make the plug, make 2ndary pieces that can be bolted/bondo'd/glassed onto the plug (adjust tunnel depth? lifting strakes "on the fly" for dial in), the possibilities are almost limitless, and far less time consuming then the old ways.

Depending on how tricky you get with the mold after the fact you can have inserts that are machined to go in there as well, easily, quickly and most importantly "accurately." (Everything is "blue printed" from the get go, which makes changes easy to document understand and caplitlize on) If it was me using this process, I would make the mold way deeper and over sized then necessary with a modular style system of inserts to allow for Dial in (bolt in CNC'd inserts), varying tunnel depth (between the true tunnel / vs pod) etc..

RD

Originally Posted by wrinkleface (Post 3612216)

not B'n a cat person, what does the pod/no pod mean, do, etc???????:cartman: Thanx

Originally Posted by offshorexcursion (Post 3612230)

Its amazing how much influence OSO has...........:party-smiley-020:

Originally Posted by wrinkleface (Post 3612216)

not B'n a cat person, what does the pod/no pod mean, do, etc???????:cartman: Thanx

Originally Posted by wrinkleface (Post 3612216)

not B'n a cat person, what does the pod/no pod mean, do, etc???????:cartman: Thanx

Originally Posted by maxonmike (Post 3612317)

Wrinkle, don't feel bad about your question... I own a Cat and I have no Idea what a Pod is either.... I see it in the pictures but... WTF IS A POD FOR????? WHAT ARE THE PROS AND CONS OF A POD???? Something I will definitely ask when I go to the Miami show...

Originally Posted by RiverDave (Post 3612320)

Historically speaking, a true tunnel will have some speed the boat "hops / porpoises" at. They generally gotta power through it, or stay below it for a comfortable ride. There are mfg's that claim (read that as all of them) that there is zero porpoise at any speed. For the most part, let me set you straight.. they are full of ****.

Center Pod boats are generally don't hop at most speeds. There is little to no hop.. (this doesn't mean their aren't center pod boats out there that do it, just saying generally speaking). 2nd benefit to the pod is slower speed handling characteristics.. If it's a good pod boat, the boat is very docile at almost any speed. True Tunnels are not.. and are less forgiving

Downsides to the pod is Big Water. What we consider "Big" at Lake Havasu or other inland water ways isn't remotely close to some of the big water east coasters run in. The tunnels are shallow and fill up fast. True Cats have deeper tunnels then center pod boats, and the depth of the tunnel becomes crucial.

To talk tunnel depth for a second, It isn't 6 inches of tunnel = 6 inches of chop.. The depth of tunnel vs how big of water is almost exponential. Every inch counts, and inches can add up to feet of chop that a boat can soak up. This is going to get into a very long conversation about tunnel compression (lifting the boat out of the water), aerodynamic vs hydrodynamic lift and a whole bunch of stuff I'm certainly not qualified to talk about.. LOL

Pod Boats = docile, little to no porpouse
True Tunnel = Big Water (claimed faster, but let me save you the suspense it's BS, HP to HP they run the same if anything certain Pods run better)

Pod guys will argue theirs turn better. I'm inclined to believe (after taking Tres's course and talking to him about it, and not just taking his word for it, but understanding the theory behind it) that True Tunnels will probably turn harder if you know how to drive them. I've driven plenty of Pod boats, but am almost embarrassed to admit, no experience driving in a true tunnel.

One BIG upside to a pod is you can run a single stern drive..

Finally the thing that is so dumb about the whole argument.. Most center pod boats from the west coast actually get their Heritage from what's called a 25 Talon. Now made from an East Coat mfg Hustler. If it's 28' and below you can bet and be right 90% of the time it's a direct Talon splash or what is called a "derivative." (direct Talon splash.. LOL) Even a lot of the scaled up (28+) Center Pod boats you can see remarkable similarities to the Talon design.

I've said about as much as I can say on the bottle, or throttle depending on how ya look at it, without getting myself in trouble. LOL

Sorry for the scattered post, I've been drinking in the garage tonight while working on a buddies Rhino. .

RD

Originally Posted by RiverDave (Post 3612320)

Historically speaking, a true tunnel will have some speed the boat "hops / porpoises" at. They generally gotta power through it, or stay below it for a comfortable ride. There are mfg's that claim (read that as all of them) that there is zero porpoise at any speed. For the most part, let me set you straight.. they are full of ****.

Center Pod boats are generally don't hop at most speeds. There is little to no hop.. (this doesn't mean their aren't center pod boats out there that do it, just saying generally speaking). 2nd benefit to the pod is slower speed handling characteristics.. If it's a good pod boat, the boat is very docile at almost any speed. True Tunnels are not.. and are less forgiving

Downsides to the pod is Big Water. What we consider "Big" at Lake Havasu or other inland water ways isn't remotely close to some of the big water east coasters run in. The tunnels are shallow and fill up fast. True Cats have deeper tunnels then center pod boats, and the depth of the tunnel becomes crucial.

To talk tunnel depth for a second, It isn't 6 inches of tunnel = 6 inches of chop.. The depth of tunnel vs how big of water is almost exponential. Every inch counts, and inches can add up to feet of chop that a boat can soak up. This is going to get into a very long conversation about tunnel compression (lifting the boat out of the water), aerodynamic vs hydrodynamic lift and a whole bunch of stuff I'm certainly not qualified to talk about.. LOL

Pod Boats = docile, little to no porpouse
True Tunnel = Big Water (claimed faster, but let me save you the suspense it's BS, HP to HP they run the same if anything certain Pods run better)

Pod guys will argue theirs turn better. I'm inclined to believe (after taking Tres's course and talking to him about it, and not just taking his word for it, but understanding the theory behind it) that True Tunnels will probably turn harder if you know how to drive them. I've driven plenty of Pod boats, but am almost embarrassed to admit, no experience driving in a true tunnel.

One BIG upside to a pod is you can run a single stern drive..

Finally the thing that is so dumb about the whole argument.. Most center pod boats from the west coast actually get their Heritage from what's called a 25 Talon. Now made from an East Coat mfg Hustler. If it's 28' and below you can bet and be right 90% of the time it's a direct Talon splash or what is called a "derivative." (direct Talon splash.. LOL) Even a lot of the scaled up (28+) Center Pod boats you can see remarkable similarities to the Talon design.

I've said about as much as I can say on the bottle, or throttle depending on how ya look at it, without getting myself in trouble. LOL

Sorry for the scattered post, I've been drinking in the garage tonight while working on a buddies Rhino. .

RD

Originally Posted by johnlomant (Post 3612390)

Dcb is a first class no matter what they produce. They put together one of the best boats period. If you have seen one in person you would agree.

Originally Posted by Hydro (Post 3612754)

I have owned a DCB and Skater. The DCB looks pretty, but when you look at how differently they are put together. Skater is stronger, lighter and faster. I started with DCB and then bought my Skater. I have owned my Skater for ten years and I have over 800 hours on it. I wouldn't buy another DCB. Just wondering if any Skater owners would switch to DCB?

Originally Posted by Hydro (Post 3612754)

I have owned a DCB and Skater. The DCB looks pretty, but when you look at how differently they are put together. Skater is stronger, lighter and faster. I started with DCB and then bought my Skater. I have owned my Skater for ten years and I have over 800 hours on it. I wouldn't buy another DCB. Just wondering if any Skater owners would switch to DCB?

Originally Posted by Havasu Hangin (Post 3612791)

Don't say anything negative about DCB or Dave will delete your posts.

Wait...he can't over here. Carry on.

Originally Posted by thisistank (Post 3612673)

Jeez Dave, who knew you were so smart!? Come on, where'd you copy and paste that from!? :lolhit:

Originally Posted by RiverDave (Post 3612813)

Rocky's pic with the vette was epic.. LOL

Originally Posted by RiverDave (Post 3612814)

I learned it all from Havasu Hangin back in the Hotboat Days.. :D

RD

Originally Posted by Havasu Hangin (Post 3612837)

I had that picture sent to me a year ago or so. Pure comedy!



The ole Hot Boat Dave would have been all over the truth!

Sadly, he went from "the man won't keep me down!"...

...to "I am the now man! F-you!"

Originally Posted by Steve 1 (Post 3613142)

Wrinkleface Now for cats which were the Second boat invented by man, when he could not stand on a his single log, so he tied two together, Look at the OSO advertisement up in the header on your right, you will see a cat “without” a pod or obstruction in it’s tunnel.

Now on a cat we have these two “fine” should we say hulls (sponsons) which are a big part of this boats efficiency,
You see we pay a horrible price for every Single square inch of wetted surface; the trick here is to keep this to a bare minimum,

Now just sticking some structure in there is going to cause drag in both the wetted and air resistance sides, No Magic here a price will be paid! For the wetted Side one would need to look at its angle of attack and the dihedral, Air flow we look at the gross cross-section, and then factor in shape, but that all goes out the window when you try to drive that Pig hanging down through water at high speed. The pressures = Resistance is amazing!

I have done testing on my outboard cats, the triples we needed a deflector system to protect the center outboards midsection (which is not made to run IN the water) I tested the boat using two engines Both before and after I glassed it on, made a - 6 MPH difference and the military boats loaded were only running @70 MPH in the Hot Air and Water over there.

Yes Years and Years back I read Talons advertisement where they claimed the water and Air being forced around their “Pod” actually increased the boats speed!!! Must be a “Magic Pod” anyway we got a good laugh out of it.

I have spent a lot of time on tunnel design on my outboard cats where I had to use everything but the dust in the air, you keep it simple, no complex shapes, the boats projected mass is what you start with here.

Originally Posted by RiverDave (Post 3613160)

That sounds great and all except there's a few problems with it.

I.E. the "Tunnel Tab" would be a great argument here.. Most people think a Tunnel Tab is to help a boat get on plane or reduce porpouse. It's not, and can actually be a ridiculously dangerous if you're driving around with it down and water fills the tunnel and hits it.

In a true tunnel application, what the tab is actually for,(when racing) if the water is smooth enough they can drop that tunnel tab and raise "tunnel compression" lifting the boat further out of the water (hydrodynamic drag is greater then the aerodynamic losses) and pick up quite a bit of speed.

On some models of boats with pods out here on the West Coast they are equipped with 2 smaller tunnel tabs to create the same effect. Problem is people try to use them as trim tabs and end up barrel rolling boats every now and again.

That in itself kind of blows the sticking anything in the tunnel will slow ya down theory.

BTW for efficiency purposes.. Eliminator Daytona (Pod Boat) single Merc 502 (415HP if memory serves?) with a black hawk drive ran in the mid 90's..

Talon with a single HP 500 is upper 90's? (I think Hustler actually claims 100mph?)

RD

Originally Posted by Steve 1 (Post 3613168)

Lets see;Now if I put a blockage in the Tunnel here on this Cat ,it would have run faster?? a Magic Pod?? Magic water? Running in a vacuum?

http://www.youtube.com/watch?v=h1csGLgX4tk

Originally Posted by RiverDave (Post 3613170)

Do you have a video of something that wasn't filmed from a handicam off the screen of an old tube TV and is actually in this millenium?

RD

Originally Posted by Steve 1 (Post 3613171)

LMAO That was video off a chopper

Originally Posted by RiverDave (Post 3613175)

I figured I made my point with the dinosaur joke, but ya missed it. That video was filmed by some guy reliving 1989 with a handicam pointed at his old Tube TV set playing a worn out VHS tape.


You're right. I do not have an american championship or a UIM world title.. But I did spend the night in a holiday inn once? And it wasn't back in the cocaine cowboy days of miami, so I guess it is what it is.

If you don't think you can increase speed on a boat via a tunnel tab, or raising tunnel compression you're misinformed. Certain Pod boats are not just raising tunnel compression, but adding "stability" with hydrodynamic lift across 3 surfaces.. Other pod boats (very raised Center pods) are raising tunnel compression with an aerodynamic surface that also helps with buoyancy and rolling over on plane (without the inherant dangers of a giant tab at a steep angle of attack that a roller can hit at speed), some are a mixture of both actually taking advantage of the water being shot into the tunnel off the sponsons and creating a little lift off that as well, etc.. etc..

There's a little more thought that goes into the center pod for the good mfg's then "Hey lets shove a giant brick down the middle of this thing and sell it." Or in your case "Hey lets deflect the water from our center outboard.. Oh we lost speed, all center pods must suck now."

These guys have been testing and dialing in their bottoms in some cases for 30 years. With the invention of the "go pro" camera the smart guys are sticking them in the tunnels facing backwards to actually see what is going on down there. Before the go pro, the high end guys would stick several pressure ports in the tunnels and data log pressures of what's going on and where down in the tunnels.

Example of a view on Bill Auberlin's 32 Spectre (true tunnel) at 170 mph, only vid I could find on youtube.

http://www.youtube.com/watch?feature...&v=mP-m2qdthEM

Here I'll throw ya for another loop, what some have found out is at a relatively low PSI of tunnel compression (true tunnel or not), the air will actually create a cushion (high pressure zone) out in front of the running boat and a lot of the air you think would be going in the tunnel is actually being pushed over the top and around the sides of the boat which means there's a lot more to be had in making the deck designs more stream lined.

But lets say you're right and there's no benefit, then at least 50 mfg's of performance orientated boats on the West / East Coast / and in between are all doing it wrong and are idiots.. Guys like Bob Leach @ Eliminator, DCB, American Offshore, Hustler, Magic, Conquest, etc.. Think about that for a second.. How many thousands of boats and millions of dollars into tooling, and all of them are 100% wrong according to you. Arrogance isn't even the right word for that line of thinking.

There are benefits to a POD (in smooth water applications), and there are benefits (speed, getting on plane, curing a porpouse in smooth water) and dangers of a Tunnel Tab.. It is undeniable. As well there are benefits to a true tunnel!

3 quick thoughts.. 1. when you won those titles did Tunnel tabs even exist? 2. have you ever experimented with one on a true tunnel. 3. Have you ever experimented with a real deal "pod" as opposed to just trying to deflect water away from an outboard?

If you're going to build a boat for big water, build a true tunnel every time.. (which in offshore racing is what you would want) But to say there's no benefits to be had from a center pod on an inland water way (or smoother conditions) is incorrect, and I don't care how many titles you have.. They aren't applicable to the conversation.

All that being said, even though I'm a West Coast guy and I understand the Pod and some of the thought processes that go in them (I'm no expert by any means). If I was gonna haul ass, I'd want the true tunnel, I think they handle better at the higher speeds, and more useful because you can run them dual purpose in the ocean and on the lake. However I wouldn't look down my nose at a pod boat and call it inferior, because there are times when they are in fact better.. Like say a single engine application on a 28' or less. How the hell would you even build that with a true tunnel?

I expect all that typing probably changed your mind not even a little bit, so needless to say I'm done talking about it. I don't think your views will change, and let me tell you for a fact mine aren't gonna.. So we should agree to just disagree and move forward.

RD

Originally Posted by SkiDoc (Post 3613232)

Steve,
You obviously know a lot about tunnel hull design. Do you think you would be able to meet DCB's west coast customer bases demand with a true tunnel design? I think it would be tough. What would your hull look life if your customer demands were:
-wants 30's in size with twins IO
-needs good low speed manners, needs to maneuver comfortably 40-60mph, since will be used mainly in crowded narrow lakes
-needs room for 4-5 adults, kids, the dog, big cooler, 5 amps.
-has to have a cabin with a couple of benches and pad big enough for 2, the wife won't have it if it doesn't have a cabin
-some may require an open bow
-needs to look sleek and racey
-needs to be a 9'beam to be trailerable and fit inside a garage
-customer thinks it should run 130's with 700's
I ask this with the utmost respect, because I'm not sure it could be done with cg forward. If you could meet this criteria, it would be huge for us all.
-

Originally Posted by Steve 1 (Post 3613228)

Originally Posted by RiverDave (Post 3613518)

Well mr Steve I'm not sure what to tell you.. Enjoy living in 1992.

RD