You have to forgive them. English isn't their first language as they say. This plane requires standard hobby type Nitro fuel and NOT gasoline like goes into an automobile. You can use either a 2 stroke or a 4 stroke engine as they say where they say 2c or 4c meaning 2 cycle or 4 cycle.

This means that something like and OS .46AX would be right at home on this plane. Sizes recommended BY THEM are .40 2 stroke up thru .63 4 stroke.