Here are a few more alternatives..
Such animation, so that we know what we are talking about ..
Well, here's the crosshead but it's applied to my new 4 stroke ... we gain a lot ... for my experience with this engine, we now get 1 liter capacity of the main piston, about 300 hp at 5000 rpm.
Of course without NOx, because the pistons will be cooled with water ..
Well, that's what to fight for ...
Andrew