RE: 1/2A Size Boat Club
I wouldn't worry too much about having enough power out of a TD to get up on plane.
When I built my first Atlas, it had a TeeDee engine. Built as a free runner without any radio gear the thing would really scoot. I set it up for circles and once the engine could hit it's power band it was off and running hard. Clean off of the water with the rear wanting to lift. If I set it for straight running to chase with the fishing boat across the lake, the modern 9.9 horse Merc would run neck and neck with it, and that was no slouch. I knew if I was able to adjust the prop shaft more parallel, even more speed could be had but with a solid driveshaft that wasn't possible.
Weight is a serious issue though with this boat. I played around a little at the time by adding a D cell battery for weight in the compartment straight behind the engine bay. It didn't like that too much. The sponsons got up on plane okay but having that weight took away all the speed and even though the engine was trying it just was too heavy and draggy to have any kind of exciting speed about it. I was also using a full 1oz Perfect tank.
Micro radios, if you go with a Berg Micro Stamp reciever and a couple of 9 gram servos, a small 4 cell AAA pack or a LiPo pack I guess is going to weight not even half of a D cell. If you search the 1/8A & 1/2A Airplane forum you will have all the answers on what the lightest combo is out there for a RX package.
I won the Atlas and Thriftway yesterday. I now have a complete Atlas kit and a partial Thriftway kit. I need the templates for the Thriftway. All it looks like is there is the mahogany deck and some sheet scraps. Other than that it is complete with a really nice box. Dang I was jumping up and down when I won. I got both kits for under what just either of them go for seperate. All snow white decal sheets and unmolested cowls, no attic stained boxes either. Fresh as todays. Schweet!
When I build my Atlas I'll be using that .098 wire or cable and an Up the River strut. By putting the strut through the bottom of the boat but keeping the front of the prop clear of the transom I should be able to raise and lower it plus get the right angle for zero trim problems. I am also planning on cutting the whole thing out of 1/32" ply plus lightening holes. If a radio box is kept to just adding a lid to one of the compartments there should not be too much weight added. I might end up keeping the servos by their locations and going with just a small box for the RX and battery.
Keeping the Dumas water jacket out of the picture could help also, and just go with a Cox finned heat sink. However when I ran mine with the heat sink the motor seemed to get too hot anyways and wanted to sag a little so I stopped using it and went back to the cool clamp.
Starting these, I just flipped with my finger. My TeeDee was used to running circles on my control line so it started first pop usually. They have to be hot for that to happen though. The first run was always a pain because of the cold engine. That's where I think a starter and a large O ring around the flywheel would have helped. String starting was a popular way before electric starters though and probably work okay with this if you had someone to hold the boat while you try. I bought a little 1/2A starter and going to machine a V groove pulley at work for it. That will be a total luxury when I go to use it. I would look into something like that if you get frustrated easy with starting.
You're probably not going to see any blow-overs with the Atas, but your going to see more than water puddle off of it that's for sure.
I can't wait for the new babies to get here....