Wanted urgently a O.S 61FX with
E-4010 Muffler engine old or new?

looks like u are gearing up for SAE aerodesign....?? first the Magnum.61 the OS .61....??

try out OS at spherehobbies ....

as of now its coming up as my list of best LHS....!!

yes..I am participating in SAE Aero design west event..and thank for your help.But it is not avilable in spheres hobby