Sure, their engine and they can claim whatever they want.But I have the right to disagree. V4,v6,v8, inline twin, inline 4, 2-stroke, 4-stroke they all have different torque,power curves and characteristics, and there is big difference between Petrol/Gasoline and Diesel engines as well. BUT, they all are considered as internal combustion engines that convert translational motion into rotary motion.