Probably something to do with the fact that you can pull over, in a car......
no.
a propeller is most efficient at about 1700rpm.
modern aircraft engines push that a bit to 2500 rpm.
an engine that develops best torque around those rpm needs to have a large diameter cylinder.
getting even combustion across the piston face requires more than one flame front so twin ignition is used.
some motorbikes have 5 spark ignition points.