Nope, it's the design of the engine. The number indicates the
number of cylinders, while the V indicates that the cylinders are
at an agle to each other with half the number of cylinders forming
each side of the V shape.
Apart from the V, there's also straight engines where all the
cylinders travel in the same direction and flat (or horizontally
opposed) engines where the cylinders travel sideways, half in one
direction and half in the others (think of it as a V engine spread
so wide the V becomes a flat line).
