RE: Best 26cc Engine
If you have seen the video of qq yak with evolution 26 equipped with canister, you can fairly say that there is a little shortage of power. With pipe evolution/mvvs should do it easily. I have MVVS(Evolution) in my 5kg Epsilon stunt with modded pipe and carb and it's swinging 16x12 8600rpm.
If you cant install pipe, I suggest that you take a look for this new syssa engine.