I just wanted to know if there is a chart or scale anywhere that gives a basic crossover from glow to gas.  Just like when you buy a kit the manufacturer will give you the option of a 40-60 2 stroke or 60 to 90 4 stroke. 
The Top Flight kit for the 1/7th P-51 calls for a 90-1.20 4 stroke.  I am guessing there is no conversion tables that show a 1.20 4 stroke glow would convert to a 20/30/50cc gas.  I wasnt concerned with brand loyalty at this point.  That all comes later.    Thanks for the input fellas.  </p>