I am not sure whether this falls into Model Engineering or Stationary Engines categories.
I watched with interest a Stuart Turner Sandhurst open-crank engine fetch =A31200 on eBay yesterday and after studying the blurb I found it was 150cc and capable of several BHP. I thought it was a scale model of a larger engine and maybe it was, but it could also be a full scale engine in its own right. I know a little about ST as I have built a little Stuart-Turner V twin steam model from a kit, and have a Stuart- Turner P5 generator for emergency house power, but I don't know much more about the range they produced.
So, my question is, are Stuart-Turner the only company that seem to make engines (or engine kits) ranging from scale model to full size without a gap in the middle ?? If they made full-scale and models then I could understand, but they seem to have pitched some in the middle where you are not quite sure if it is one or the other - which seems most unusual.