Originally Posted by
jrwoodchuck
i like the 4-stroke idea, but i would be worried about the valvetrain in a crash. though you can gear the piss out of it, 4 strokes are all torque. about 10 years ago i had a 4 stroke x-cell (ys 91) in a 60 size heli. crazy crazy grunt, plus YS are fuel injected (sort of, they presurise the tank to 6 lbs) it would pull 14 degrees pos/neg of pitch (1750 head speed on a gov) all day long. for those that don't know heli's, "THATS STUPID POWER". and get 25 min of flight time on a 26oz tank. (10 min if 2 stroke) I would like to see ringed engines though. i'll get 20 gallons out of a heli engine, buy a $20.00 ring, and BLAM-O!!!! new engine!!!!
I asked this question too, the gist is that the rings wouldn't survive the RPM's and relative low lubrication fuels we use. Ariplane fuels have more oil content and don't need instant throttle response that's required in surface use. Would be nice though.