i got a thunder tiger expo 3D at a auction and a was wandering what size engine would give me best performance, i was thinking of putting a O.S. 46AX in it do you think that would be a good engine for it??

isnt the expo an electric foamie?

no its a 46 size. its also called a 3D Spirit

3W - the Spirit will happily hang on a mere 46 ... mine had a TT46 and my pal the 46AX. I ran an APC 11x5 and she was perfect, no balance issues too. Only thing about the plane is please change the hinges, they are what I would call ... 'plasticky' ... not much fibre to it and my pal's one came off when he accidentally kicked the elevator. When you put the tank in please be careful ... the former can crack if you push it too hard. If I had an engine to choose for the plane I will go with an ASP 52, its cheap, reliable and powerful, runs on 5% nitro. Will turn a 12x6 with ease. Do check if the engine will mount into the rails with ease ... the crank is slightly wider.

i got it pre built so it would be hard to replace the hinges and the tank is already in the plane.