RE: McCulloch 32cc on a 85" 17lb Extra 330?
You can get more power out of the McCulloch if you convert it to gas/glow hybrid and use an APC 18x6W prop, you can also shed an extra pound off by eliminating the heavy flywheel and coil, I suggest that you replace the original heavy muffler for an aluminum one, if the plane is at 14.5 pounds it should fly good with the Mac converted to GAS/GLOW hybrid