A .46 will over power your trainer. You'll be running at low power all the time. Save that great .46 for a low wing, second plane like a 4*40. The .52 4-stroke will be perfect.

Someone out there needs to go weigh some 4-strokes. Mine are lighter than the same size 2-stroke. OS .91FX and Magnum .91XLS with muffler-26.5 oz. Magnum .91FS 22.5 oz, Saito .91 19.8 oz.

If you are talking equivalent power in the .46 range, my .46 engines weigh in the 17.0-17.7 oz. My Saito .72 weighs 18.2 oz, but it is probably that little much more powerful than the .46. The .82 is even lighter.