I think my next project will be my first try at a flame licker, the Poppin engine in particular. I looked at the plans and I really don't like how small this thing is and I want to scale it up about 50% to make the parts more manageable and avoid 2-56 threads. Therefore the question: Being that the engine's displacement will increase by 2.25 because volume increases with the square of the diameter, will simply scaling the entire engine 50% work or do I need to have a cylinder displacement scaled 50%? Thanks in advance for your knowledge and reply. ...Ved.