A touch more umph? the zenoah isn't even as powerful as the zdz 40 rv-l.and yet its two pounds heavier.
I'm sorry to say this but you will probably will be able to fly this plane with this setup, but you will be missing out on the true feel and performance that this plane can offer. The DA-50 would not only be the best engine for this setup, but it will also be the easiest and by far one of the smoothest running engines in this class.