Kenneth,

I also agree with most of what has been said about engine selection. There is nothing that sounds better in a bipe than a good throaty 4 Stroke. But, since you are just getting in to the building and flying -- 2 Strokes can add some real advantages. Additionally, a GP Skybolt is going to be a handful as a second plane. I spent about 10 flights on my dad's Kadet including 5 with his symetrical wing. I learned while I was building my Super Sportster 60 (Tower .75 2 Stroke). Though I have learned a lot this year and am getting really good on my Sportster (most patterns) it also came at a cost. 7th flight -- confussion -- upside down -- thumbs the wrong way and she was 8 inches deep in a cotton field. She was jsut flying -- my Dad yelled UP UP and splat! She is rebuilt (3/4 of a new wing, new tail feathers, body spliced back together in two spots, 8 oz heavier) and continues to fly well.

Just remember that as you go the 3 or 4 step is recommended because bipes and performance aircraft are fast and unforgiving. The Spotster is considered a good second plane and moving to it after just a few flights on a trainer was a handfull, a bipe will even be more. I would hate for your dream plane to produce a cloud of balsa. As far as building, I am also a software engineer/integrator. Follow instructions -- relook at everything twice -- good fitting parts and clamps cut down on glue which is the real killer for weight by in-experienced builders -- and you can build a great plane!

No as far as 2 strokes go, I will probably catch a little flack for this. 60 Size and below you just can beat a good 2 stroke. Lots of guys at my field fly 4 strokes and I will tell you, they require a lot more maintance and the only guys that seem to have engine issues are the 4 strokers. I am not saying that 2 strokes are better, they are just easier and less expensive until you know that your addicted and your not smashing planes. My dad has several 2 stroke 40 - 60 size engines that even after 20 years they still scream and all the maintenance can be summed up into a couple of glow plugs.

Now as far a 4 strokes go, there lots of options. A couple of guys fly Magnums and they seem really strong. At the price you just can't beat them. OS and Siato are the big guys on the block and you won't be disappointed but they are a little pricy. Finally there is a new engine manufacture that builds a different type of 4 stroke. This is RCV. There four stroke engines use a rotary valve system instead of poppet values. Most of the issues with the four strokes at the feild are valve issues or timing. The RCV CD sieries a just slightly taller than a 2 Stroke with only one more part. They have a good warantee and are priced about the same a OS/Saito. The really cool engine they carry is the SP engines. These engines use a piston that cycles front to back and are gears at 2 : 1 which means that a SP 90 turns a 16 to 18 inch prop at about 4000 RPMs. These engines can almost certainly fit in nearly any cowl. I am not recommending the RCV and I don't know anyone who flys them, but my next warbird will probably use one.

Marc