Coverted a Featherlight 1500 last summer, love it. Really easy to convert and runs great. I turn a 15x8 at 7000-7100 RPM. Its on my Balsa USA Eindecker 80". We (fellow club members) bought 6 of these directly from Poulan's factory reconditioned store at the factory for 37.00 (9.00 for shipping UPS) and one of our members made the coversion parts for us in his machine shop. Very very easy to convert and use. They do say 16cc on the box, but the engine houseing says 25cc and we mic'ed them at 24.9 or so. These are the ones with bolt on mufflers. If anyone is interested I can look up the phone number to thier store (Or anyone can for that matter).