My first 3D plane was a "40 sized" one as well. It was similar to the U can do. Not knowing any better I put a 46 in it. It weighed over 5lbs and flew well but nowhere near 3D power.

Later switched the 46 out for a 91 four stroke. Then it was a 3D monster.

The plane will fly well with that engine but no prop is going to give good 3D.