A topic to think about

[Carl Van Houten]

Thanks for the compliments. I have enjoyed this sport.

Is the Taboo better? It is more stable at higher speeds so yes, it is better. It's still a tunnelboat so there are some things that we are just going to have live with. Where did the stability come from? Well, if you look at it you will see that the changes made were mostly aerodynamic changes. So I would have to say that the improvements were 90-95% aerodynamic. If you look at the first version Taboo and compare that to the last version, the changes are to most people hardly noticeable. So don't expect to see a drastic difference in appearance. But compared to the aero package of the Lynx it is very different aerodynamically. There was 7 years spent on the Lynx and over 10 (off and on) spent on the Taboo to get it where it is today.

The reason for my thread is to inspire others to get interested in boat design and theory of the outboard tunnelboat. I just want to see people to start thinking about the complete package. The days of buying a $100 outboard and building a $35 kit tunnelboat are long gone. Now that we have $500 outboards and $400 boats there is no going back because even thought the price was right back in the day you could never expect to show up with a K&B 3.5 on an old 1979 model tunnelboat and expect to blow everybody away.

I will continue to produce the models I have already released but I am probably not going to add to it. I have a couple of boats in a design state in my shop now but I have no plans to putting those into production. I am not done with the sport but rather I am changing directions. 2020 has hit our sport hard. At the moment we basically have only two off the shelf new engines to choose from. Alan's 7.5 conversion kit for the CMB gold head and the O/S 3.5cc. I'm not sure if K&B is still offering their 1" or not.

I am hoping that homeland security doesn't make nitro any harder or more expensive to get due to this latest Christmas bomb in Nashville. We don't need that.

Many have suggested that our sport needs more young people and that is absolutely true but young people as a whole take very little interest in r/c boats. I see the gas guys gaining participation strength in all their classes and many think that it is nitro cost compared to gas prices and that may be some of it but more than that I see a lot of gas guys building their boats. I feel like people who build kits really get into their hobby more because after you spend the time to build a model you are much more apt to race it. If you can't pull enough young people maybe we need more kit boats to help pull builders into our sport and maybe that will possibly pull more life into tunnels. Don't get me wrong in some areas tunnels are really strong.

Unless something changes I am not going to supply wood kits. Laser suppliers cost and shipping cost along with some logistics issues make that a no deal for me at this time. I have a 130 watt laser tube and servos for building my own laser but That is a back burner project for now.

Yea it may sound crazy for a fiberglass supplier to be suggesting that more wood kits are needed but I want to see the sport thrive in 2021.
-Carl

 

[Steve White]

^^^ Boat racing of all types is basically a red-headed step child compared to other motorsports. Lucas Oil dropped the drag boat series a year or two ago.

That being said, having worked in aerospace for a while and in the engineering community for the past 10 years our sport is perfect for "Science and Technology" in the schools. It combines Robotics with Aerodynamics as well as model building.

I'm at a point where some time as available to "get back in" to the hobby. My plan is once I get some boats running to put up a couple of flyers at work (after this COVID crap runs it's course and the engineers come back into the plant) and see if there's any interest.

My guess is there should be.

This hobby/sport could be packaged up for High School Science & Technology - it's perfect for it. Much more fun that drones and far more interesting and challenging when adding the elements of racing and nitro tuning. Battlebots is gaining in popularity, pretty exciting stuff - boat racing blows it away.

 

[LohringMiller]

I know the Seismic Racing guys. Before they designed that hull they were one of my (B&M Leecraft) biggest customers. They built a very good 7.5 size hull. I would still take a Hornet, especially for a mod engine.

Lohring Miller

 

[Carl Van Houten]

Lohring,

That is Chris Wittrig's personal boat but it is actually one of my hulls. The seismic guys run some of my stuff these days. Good guys for sure.

 

[Julio Almazan]

Hi:
Aren't we discussing the SAME, with different ways of looking at things? Don't you think that BOTH things (aerodynamics and hydrodynamics) allow the development and improvements of our tunnels hulls? Each of them has its importance ... I can't imagine a Linxs or a Dragon without BOTH developments ... functional and aesthetic ... aero and hydrodynamic improvements
My personal experience with my two somewhat old hulls is as follows:
My tunnel hull Top Speed II, with a stock engine like the Thunder Tiger 3.5cc, behaves in a very correct and very reliable way ... when putting an OS 21 engine on it, things change and it becomes a very nervous and unstable boat . My other 3.5cc hull is an HTB 290 and this one does gladly accept the OS Mods engine ... but with a stock engine, it becomes a clumsy and unpredictable boat.
Anyway, I love my tunnel boats ... for me, the best category of boats (scale and semi-scale, if you know what I mean)
I see in my future, a last generation Dragon ... the other adventure companions have already begun to change for Linxs and Taboo ... I need a Dragon to make them bite the dust ... or the water.
Perhaps, in a very short time, I will be placing an order for a Dragon hull, for the 2021 season ... perhaps very soon...

 

[Carl Van Houten]

Julio, I agree 100%. It is a combo of both working together. The working together part is where the fine tuning details come in.

 

[Kris Flynn]

I spy some ride pad mods to that HTB!

 

[Mark Poole ModVP]

I have built enough boats and played around with enough boats to know that, yes, aero makes a difference. At one point back in the mid 90's I was taking an RC boat to the water every chance I got. I was not racing, I was just building boats and running them. Changes to the deck height, deck shape, cowling size and shape all made noticeable differences in the handling and ride attitude. But I can say that what made the biggest improvements to the boats attitude on the straights and improvements around the turns was on the bottom. Adding 'boat tail' (I call it aero taper) would make a 'softer' improvement. My Mod-VP boats would not carry speed around the corners without wanting to hook until I made a simple change to the edge of the center pod and the difference was HUGE.

Carl, would you say that the XT460 was the first tuned RC tunnel boat? I believe it was wind tunnel tested before the production molds were built.

I would also say that having plenty of horsepower, the right prop and where that prop is in relation to the back of the sponsons is a big deal. I will tell you what makes me say that. When Mark Hopper loaned me his HTB 360 to race at the tunnel champs in Walterboro that thing was a rocket but handled with precision. It had a round ear prop and a long set back bracket. If you remember, Ernie Lafluer ran that same type prop and set back on his 290.

To create an all out racing machine requires that narrow window of balance that you speak of. To win races, you need that machine. What would be good for the hobby is a cheap priced but good behaving boat that goes about 40 mph. From that pool you get those who will want to race and end up having more racers. You are right, 2021 needs to be a much better year or it ain't going to happen.

 

[Carl Van Houten]

Mark,

Thanks for your input! I would say results are hard to argue with by the neigh sayers concerning the topic of aerodynamics. Maybe in my previous comments people got the impression that I was saying that "all" of the resent advances found have been in aero because I harp on that subject so much but it is the total design where desired traits come from.

If tunnelhulls were not such persnickety little demons that demand that you give them everything they want and act like spoiled children that challenge your patients to the max, I would have gotten bored with this hobby long ago and found something else to do with my time. Instead of giving up I decided to dig in and see what made these crazy boats tick. Learning is a slow process. People with no patients don't typically fool with tunnel boats for very long.

Wind tunnel? Sometimes you can see a change right away and other changes might make slight changes that may cause your boat to prefer a different prop cut or a different style prop all together, then understanding the characteristics of the favored prop can tell you a lot.

I am going to skip a response to the XT question to avoid blowing this thread. Out of respect to other designers no matter what I think about their boats, I try not to say anything derogatory about their models on social media.

Engines- Having brute engine performance can make a model appear to shine on the track. The overall field performance of round track tunnelboat racing has improved greatly over the past few years and has leveled the performance between competitors so having a boat that is obviously leading the field is much harder to obtain than in years past.

Yea ole Ernie fell off the page around 2007 if I remember right. Running 12 or 14 boats at a race will eventually burn a person completely out & Mark is spending time with his grand kids these days.

None of our tunnelboats are perfect mine or anybody else's and never will be. If they are still racing RC tunnelboats a hundred years from now someone will still have that occasional stuff that came out of nowhere and if you don't blow off every now and then you are not going fast enough. LOL

 

[Mark Poole ModVP]

You know, one of the things that would have given outboards a better reputation from many years back would have been for the hulls to be longer. Most of the old 3.5 tunnels were very short. Made for good speed on flat water but they had hooking, flipping and hopping issues. A sacrifice of a couple mph in a more stable platform would have been less frustrating. The first boat I built was big, 40" long and 15" wide. With a 7.5 it ran surprisingly well and would eat rough water. There were many times I would be at a public landing or park and people thought that boat was so cool. I would hand them the transmitter and let them drive it knowing they could not flip it.

I don't remember the details but someone won the internats many years ago with a 3.5 on a 460.

 

[Carl Van Houten]

Mark,

Over the last 20 years our 3.5cc sport tunnel boats have increased in length. You may not remember because 20 years ago we didn't go much further East than the Atlanta Spring Races but the original predecessor prototype boats we (me and Talley) first started fooling with were called the X0, X1 & X2 tunnels. These 3 boats were small (under 27" long) and back then nobody had ever seen 50mph from a 3.5cc round track tunnel.

About that same time the first O/S engines came to the U.S. Mike bought one as soon as they hit the market and we began working with them. Our X-2 was the first round track tunnel boat to ever see 50mph and it was done in Huntsville using an O/S engine.

Mike Rushing figured out how to get that engine to hit and he had a 54-55mph tunnel boat when a good 3.5 sport tunnel was still running 47-48mph at best. After that I decided (like the movie Jaws) we needed a bigger boat! That's when I built my 285 (28-1/2" long tunnel) Then as engines were tuned and props were developed Eric Betty showed up at a SAW event in Huntsville running his 285 and laid down an unbelievable 58mph pass and went on about six months later to be the first to sport outboard tunnel to break 60mph.

By then it was 2011 and at that point we knew that again we needed a bigger boat so the MR-300 (30") project was started. That boat has recently been finished and seems to handle the new mod 3.5cc power well on reasonable race water so until somebody builds a 3.5cc O/B that will man handle that boat I am going to stop at 30".

A few years back Kentley Porter pushed the 285 round tracker to 74 mph in the mod class but he could only get a one way pass at that speed. He held the SAW record with a round track boat until a few years ago.

The fastest we have ever gotten a conventional pickle fork sport 3.5 was 64mph. We are going to throw one more pickle fork design at that record and if that don't get it we will have to switch to a custom design.

You are right that it doesn't take too much wind to turn the 3.5cc tunnel class into a wave hopper event.
Those little 3.5cc tunnels are fussy little boats. I have said for years that I was going to setup a 3.5cc on one of my 31-1/2" long tunnels to have if the weekend looks like it will be windy but I have never done it. That would be the perfect setup so you could choose witch one you wanted to use but of course to stay legal you would have to stick with the one you ran your first heat with.

Okay back to work...

 

[Grimracer]

Its worth remembering Gary Preusses 50MPH 24in tunnel (the Dunny built porotype to the HotShot / Seahawk with a 8907 on it... that was around 1992ish.. 93ish or so... (man its been that long...)

First time i saw that boat run I was like.. WHAT!..LOL.. I had.. we all had.. work to do... no records were run for sport tunnel because well.. what was it.. 97 when it became a official class..

None the less.. fun times..

Grim

 

[Jerry Dunlap]

Its worth remembering Gary Preusses 50MPH 24in tunnel (the Dunny built porotype to the HotShot / Seahawk with a 8907 on it... that was around 1992ish.. 93ish or so... (man its been that long...)

First time i saw that boat run I was like.. WHAT!..LOL.. I had.. we all had.. work to do... no records were run for sport tunnel because well.. what was it.. 97 when it became a official class..

None the less.. fun times..

Grim

Its worth remembering Gary Preusses 50MPH 24in tunnel (the Dunny built porotype to the HotShot / Seahawk with a 8907 on it... that was around 1992ish.. 93ish or so... (man its been that long...)

First time i saw that boat run I was like.. WHAT!..LOL.. I had.. we all had.. work to do... no records were run for sport tunnel because well.. what was it.. 97 when it became a official class..

None the less.. fun times..

Grim

Gary won a lot of races with that boat. Had an oval boost tank siliconed to the top of the cowling.
JD

 

[Carl Van Houten]

Grim,

Gary Pruse... I haven't heard that name in a while. What happened to him?

I just asked Mike what year we did that in and he said it was 1998. I could not remember the exact year but I do remember some of the guys who were there and when we told them that our O/S would run over 50mph nobody believed us. The O/S engine was not well received at first but that changed once the speeds progressively got faster and faster. It reminded me of my dad telling me how the German Konig came to America and ran all the Mercury Mark 20-H racing engines out of town. If you have ever heard a konig run that bad boy would scream. That was the end of Kiekaehafer's line of hopped up fishing motors.

I think the O/S became available in 1996-97. Mike had his engine before Tower Hobbies had replacement flex cables in stock. After that original cable broke we had to wait 3 or 4 weeks before they got cables shipped them to us.

 

[Jerry Dunlap]

Grim,

Gary Pruse... I haven't heard that name in a while. What happened to him?

I just asked Mike what year we did that in and he said it was 1992. I could not remember the exact year but I do remember some of the guys who were there and when we told them that our O/S would run over 50mph nobody believed us. The O/S engine was not well received at first but that changed once the speeds progressively got faster and faster. It reminded me of my dad telling me how the German Konig came to America and ran all the Mercury Mark 20-H racing engines out of town. If you have ever heard a konig run that bad boy would scream. That was the end of Kiekaehafer's line of hopped up fishing motors.

I think the O/S became available in 1991. ?? Mike had his engine before Tower Hobbies had replacement flex cables in stock. After that original cable broke we had to wait 3 or 4 weeks before they got cables shipped them to us.

Gary Preusse has had medical issues(heart), but still does some RC hardware sales through G&M Models.
JD

 

[Terry Keeley]

Its worth remembering Gary Preusses 50MPH 24in tunnel (the Dunny built porotype to the HotShot / Seahawk with a 8907 on it... that was around 1992ish.. 93ish or so... (man its been that long...)

First time i saw that boat run I was like.. WHAT!..LOL.. I had.. we all had.. work to do... no records were run for sport tunnel because well.. what was it.. 97 when it became a official class..

None the less.. fun times..

Grim

Is that the one he picked up 5 mph with one of our heads?

 

[Jerry Dunlap]

Is that the one he picked up 5 mph with one of our heads?

Yes
JD

 

[Carl Van Houten]

I am 100% all in for people designing their own boats and is actually the reason I started this thread. I wanted to get people to start thinking about the "total boat design". Don't get tunnel vision and dwell on just certain parts of a boat design because you will leave too much on the table if you take that approach.

What do you think would happen if you replaced the decks on the bottom two boats with a flat deck? Do you think it would run the same?

 

[Mark Poole ModVP]

Allison's are great boats but man they are expensive!

 

[Alan Elzer]

I believe any design change is too expensive to do for just looks, just saying