The gaps are the point. On the BMW i8, open channels between the rear pillars and bodywork give air a route toward the tail, turning what might look like missing material into a feature of the car's aerodynamic design. The effect is as visual as it is functional.
Air dislikes abrupt departures. As it travels along a moving car, the boundary layer can separate from the surface, leaving a turbulent wake that contributes to drag. The i8's channels help guide flow around the rear bodywork, where managing that separation matters. They are not magic tunnels. Their contribution depends on the shape of the entire car, and no single opening can be credited with its aerodynamic performance in isolation.
The more interesting achievement is that the engineering remains visible. Instead of hiding every passage beneath a smooth shell, the i8 uses layered surfaces and flying buttresses to make airflow part of its identity. The car is a hybrid sports machine, but its rear profile tells a story that has little to do with the powertrain: speed demands an argument with the air, and shape is how the car makes it. A hollow becomes a signature. In the space between pillar and body, absence acquires a shape.
