tiddy82,
There really isn't much difference between mounting an engine on its side than there is if it's mounted upright. The plane will balance the same no matter how the engine is mounted. What you have heard about inverted engines needing a little extra attention can be true, but as far as an engine mounted sideways there usually isn't any problems with them running like that. I have had more planes with the engine mounted sideways than I can count, and I've never had any issues with them.


Ken