Originally posted by tkg
Above 40cc gas for sure, below 20cc glow is it. Between is a very gray area that depends on $$, the plane and what you are going to do with it.
I agree
Depending on the type of flying you want to do the 23 cc engines are more than likely going to be way to heavy for the amount of power they make. A ZDZ 40 cc engine doesn't way any more than a G 23 and makes a lot more power.
Between the 50cc to 150cc you will get about the same power as glow 2:1.
And it is a lot cheaper to run
and cleaner
and more reliable