RE: WHAT ENGINE IS THIS??
Yes.... I do. Poulan first starting calling their chainsaws "pro" because they started to chrome plate the cylinder, thereby increasing engine life and making the engine a little more resistant to cold seizure. I think they also went to a forged crank but not 100% on that.( see, I don't know everything after all) I assume that if their calling their weed wackers and blowers that then they are probably plated as well. Why don't you just have mr troutman chime in and tell us what model saw this came from and shut me up already.