I have been flying electric models for a while now and have come to rely on programs like motocalc to tell me what kind of motor/battery/prop combinations work well before I get off the ground. I was wondering if there was a similar program for glow engines? Are you guys relying on experience for your setups or is ther e anice little program that works well for this type of thing?

It's called run whatever engine you like within reason and sometimes unreasonable.

In our club, we say go w/ the biggest engine reccomended, 'cause the power will be there if you need it . If you don't need or want it, that's what the carb. is for, you can always throttle back. And a bigger engine can help balance the plane, because you don't want it tail heavy! Prop selection is pretty well known for a certain eng. size (there are charts + tables) or you can ask anyone here, just tell us what plane you've got, and eng. and someone will be glad to help out. Happy Landings...

I usually look at the manufacturers recommended range of engines, the weight of the plane, how I intend to fly it and then add a bit more than I think it'll take. My newest plane is a 40 size Ultimate bipe that will be powered by a Saito 72. This engine is just a bit larger than the recommended range.

Seems like I usually end up about 1 engine size bigger than what is suggested.

I would never suggest going smaller than the largest recommended engine though.

I usually look at the manufacturers recommended range of engines, the weight of the plane, how I intend to fly it and then add a bit more than I think it'll take. My newest plane is a 40 size Ultimate bipe that will be powered by a Saito 72. This engine is just a bit larger than the recommended range.

Seems like I usually end up about 1 engine size bigger than what is suggested.

I would never suggest going smaller than the largest recommended engine though.