Hello, and welcome. I see this is your first post here. Your question while valid is not really suited for the beginners forum since this plane is no where near a beginners model. Whith that said when I want to see what engine works well in a model I go look at the RCU user reviews to see what other pilots have to say about their plane. Here is a link to the reviews of your plane.
http://www.rcuniverse.com/product_gu...fm?kit_id=5252
With that said you may be able to get even more help in these other RCU forums by people with more experience with this aircraft or the engine.
ARF or RTF
Giant Scale Aircraft - General
Gas engine forum