Since mine is not built yet, I can't say what would be the best combination. I can only tell you what I plan to do. I am going to use a Thunder Tiger .46 with an APC 11x5. The Citabria should do well with a good strong .40 but that little extra power of a .46 should give better performance. The 11x5 prop will give more scale like flight characteristics.

If you are planning for it to be a strictly sport plane, go with a plastic covering. Personally, I want something more of a stand-off scale and I would like to have a fabric covering. I have not decided what type I will use but I have plenty of time to make that decision.

Good luck,

R/C Flight Unlimited