Hi Stephano, nice cradle! About engine position, all I can guess is by mounting the engine horizontally, you keep the carberator closer to the center line of the fuel tank. That ASP 1.80 fs engine is about a pound heavier than a saito 1.80, so your right, mounting it horizontally throws a ore weight to side of the plane. You could help compensate by installing battery, receiver, etc on opposite side of fuse to help balance.