I have the .45, and as far as I know pretty much anything made in the 90's was Schnuerle ported. Mine runs great, but is not going to be as strong as the modern engines. It will pull a 40 sized trainer, but you will not have a lot of excess power. I would avoid using it off of grass. The .45 turns a 10x6 prop well, but the newer .45's will turn an 11 or 12 at about the same RPM's. As long as you have a plane that will be able to use it it should be fine as long as it is in decent shape. Biggest thing is you should not be able to hear or feel the bearings when you turn it over.