Doesn't look like very much space between cylinders for airflow to the second row...Wright tried making a 22 cylinder two row.
View attachment 692129
See Wright Aeronautical R-4090 Cyclone 22 Aircraft Engine
I often think these air powered "engines" are nothing of the sort. If it's an engine it should be generating power, not consuming it.The air powered lego engine is like a double acting steam engine. Each stroke is a power stroke so an even number of cylinders works just fine. It isn't even a two stroke, it is really a one stroke...