Hey guys looking at getting an ad2 and I wonder what the specs are for an engine to just "drop" in. If I've read everything right I think the kit comes with a header for rear exh engine but i'm not sure if i need a an sg or threaded type shaft. I think I need the threaded. I was considering a Sirio s12trpaf would this motor work? Also I noticed that the preference is for a rotary valve carb but every pro motor I look at comes with a slide valve. Anyone have a good recomendation for a rotary carb I'm new to Nitro (not rc) I would like what is easisest to setup and maintain and I hear that the linkage for slide valves can be a pain.