Barzini, what part of upstate New York. just got an email on your question. I run OS46axs. I cant advise you on the props; HOWEVER, you can run two blade and three blade props with the OS55s. there is a guy, a real wizard, on YOUTUBE. his name is TINKERMANRC. He has a three part build series on youtube about building his 310. I'm sure there is information on his props and numbers for them. pictures as well. if you can reach his website, you can send him an email and he is actually quite good at responding to questions from 310 owners. this would be the fastest route. also, there is a build number for Topflite in Champaign IL. its in the build manual for the plane, and may be on Tower Hobbies website. the Topflite tech guys should also tell you which props to use. Finally, as a third choice, id write something on RCGROUPS.COM asking which props to use, and you will get lots of replies. be specific in mentioning your engines. there is also a complete BUILD THREAD ON RCGROUPS.COM, if you need additional information. OK. tinkermanrc, Topflite in Champaign, IL; and, RCGROUPS.COM. that should get you the info.
AS A PS: I researched the OS46ax against the OS55ax. if I remember correctly, the stroke was a bit different with the 55's, yet power wise, and speed, the change was minimal. IMHO, I think OS just came out with another engine to just make money. I like the OS65, but the mounting, the cutting of the nacelles, etc, for me, make it prohibitive. OS65's would really be a lot more power, but I don't want to sacrifice the plane. if you know of any 310 topflite kits that are complete, and not started, let me know. thanks. hawkeye.