Air Traps, Tunnels, and Bringing a boat back to life

[KyleMalmin]

I am completely reworking a old hydroplane hull my father and I made over 20 years ago. Probably would be better to scrap it but its got memories so kind hard to do.

I've got a big project on my hands. The bottom hull needs to be completely replaced. Because I'm going to have it all torn apart thought might as well try to improve it. Oh it is the old heavy "wetback" design.

I've noticed that most of the new hydros have air traps going from the sponsons to the stern. Seems to make sense to get more lift. How far do these traps typically stick out from the bottom at the stern? Are they up to the sponsons in the front? Are they made of plywood usually? Do they hold up and does this not create digging in while turning?

I have also noticed that some of you are adding small tunnels at the stern - last 15 to 20 inches. Does this create less drag?

I know this probably sounds like a crazy project, but my father and I made the boat and it was good times. The boat will never race too heavy, buy a lot of fun.

All advice appreciated,
Kyle

[1100-one]

Kyle,
Im sure you will get many answers on this to help you. Darrell Sorenson could help you as he is a boat builder as there are many others. I seen he had his number on the site with the Japenese racing post. He is CSR4C on member list.

Todd

[3autility]

old hydro

I had a Wetback that I added airtraps to . The boat was too heavy and was a dog so I eventually got something better. But if you are restoring something that has been in the family, then go for it.

[KyleMalmin]

It is crazy heavy. But I just can't bring myself to bringing it to the dump. Thought my girls could play around with it.

Then later I plan to build another up to date boat after restoring this one.

How did you end up doing the air traps?

Kyle

[KyleMalmin]

Cut into the hull after church today and it wasn't pretty. Thought that just some of the plywood needed replacing, but whole frame is beyond saving. Kinda sucks. Got good memories but the boat is going to the landfill. Never thought that would happen.

Anyway I don't have a need to know about tunnels and air traps. I have nothing to put them on.

May build or buy an used hydro. Haven't decided. Got a 25xs but its the old long exhaust. And that doesn't sound like its raced.

I need to regroup and figure this out.

I appreciate everyones help. This site is exceptional. When my dad and I first built our "Wetback" hydro we really were completely on our own. Wish we had this site back then.

Again Thanks,
Kyle

[bh/]

That is unfortunate, but to be expected. A boat of that vintage was probably fastened with hundreds of 'anchor-fast' nails, and if u tried to pull them out, the frame comes with it, and taking the bottom off and leaving them in is a labor of love.
Hal Kelly's Wetback, within its limits, was a good boat for its time. Some of the amateur builds were quite heavy.
If u really need one, Clark-Craft in NY still makes a kit for it, and some home builds show up occasionally on the collector sites.
But it is sorta like getting a new puppy or kitten;
-why get one from a breeder, when there are lots of others out there looking for homes. This site regularly has older race boats[ie; 10 +years] for sale to deserving homes, spayed/neutered, all included.

[KyleMalmin]

Yes, that is what we did. We bought the kit many years ago. It is full of nails. I was going to grind all the nail heads off and pull the plywood. But when I started it was obvious the entire frame had rot.

I still have the plans for the boat, but thought it would be kind of backwards to rebuild another. When we built the boat we didn't know a hydroplane from a runabout. So mistakes were made. Mainly made it too heavy. It was a head turner, but never able to race.

Looking for something newer I guess and probably in the CSH class. (class and motor equivalents aways confuss me)

I wiegh about 180 so I need something big enough to handle all the extra sausage gravy and biscuts in my future.

Kyle

[KyleMalmin]

Haven't decided if I want to build or buy? Looking for a CSH class.

Plans I'm thinking of are Rick Fralick plans or MJR plans. Thoughts?

If I don't build I would be interested in buying. Any boats for sale out there?

Have a 25xs but want something that could work with a 302 if I change over.

[Aussie Steve]

here's one mate, it will be freshly clear coated when you pick it up ...make an offer .

Steve A

https://hydroracer.net/forums/showthread.php?t=19781