I purchased a Stihl 028 Woodboss chainsaw to convert. It has points and a condensor under the magneto that are triggered by a lobe on the crank. I think it's about 55cc.

I purchased the saw for $30. It came with a carrying case and an extra chain. Missing carb and breather element.

I got the carb and other parts for $15 from a small engine shop. Total investment was $45 for a pretty nice saw.

I just had to try it out, so I took it to my Dads place and we cut up 2 pickup truck loads of wood in a weekend with my saw and his Poulan Wildthing saw.

I think I'll look for a different saw to cut up. $45 for a nice chainsaw that cuts like a razor is just too good to cut up for an airplane engine.