Midstar 40 engine size ?
 

Im building a Sig Midstar 40 and have not bought an engine for it yet. The plans call out for a 30 to 40 2 stroke,I was wondering if the 40 is going to leave it under powered flying off grass. I have an Avistar and had some problems getting off the grass, so i put a O.S.46FX on it and it is a rocket. I have a O.S. 40LA off my Avistar but if its going to be under powered just assume not to mount it.
Open for suggestions ---Thanks

RE: Midstar 40 engine size ?
 

A OS40LA will be underpowered,most of my flying buddies are using OS46FX,plane flies great. On mine I have a OS70 4s,which I really like,a friend of mine as a OS61FX on his,lots of power but had to move the engine down which changed the thrust line,now the plane isn't as aerobatic as it once was,hope this helps.

RE: Midstar 40 engine size ?
 

I had a TT .46Pro on mine and it was a beautiful combination as it really performed!!!! I really don't think that you'll be happy with the .40LA.

RE: Midstar 40 engine size ?
 

Well Wheelpant here we go. It would depend on what you want to do. If you want a smooth flying plane that you can do lazy aerobatics with a simple 40 would do. A friend of mine had an older OS 40 FP in his. It flew very well, It was not overpowered. It Flew gently and real stable. It did not have a lot of verticle or extra power. I think the TT 46 pro would be a good choice.

My plane has a MVVS 40 with a tuned muffler on it. I also added wheel pants (neat hugh!). Runways are almost optional for take offs. When you break ground you had best be ready with opposite ailerons to counteract the torque of the engine. It posativly screams with an APC 10-6 on it. If I were to play with props I think it would hover. I am also using 10% fuel too. I think this is overkill, The plane has been flown through the intermediate pattern by someone more Qualified than me. It also really humms along in level flight on the pipe. Gotta be pushing 90 or more MPH. Well i hope this clears iy up some. I will tell you the addition of wheel pants did make a big difference in smoothness. Several people who had one when flying my plane have admitted it is more smooth and tracks better.

Mark Shuman