I'm surprised the BRZ doesn't incorporate those BMW 1-series side vents on the front bumper. Maybe it does though. I wonder if they let the Prius division work on aero for the car.
Lots of modern cars have some tricky aero touches that are hardly noticeable.
Obviously it has a smooth profile so flow separation will be a non-issue in this car's speed range. The profile ends with a sharply cut trunklid, slightly turned up, an effect that is more pronounced with the optional decklid spoiler.
Nobody ever pays attention to roofs but they're important. These cars' roofs have a channel in the middle that acts like fences you might see on the roof of a race car or a raked airplane wing, keeping airflow in order over the curved surface and preventing it from falling off the sides. This helps make sure that a higher volume of air will be directed toward the rear decklid/spoiler/wing.
The channel spreads out a bit toward the rear, having done its job over the roof. Because of the tapered greenhouse and sloped side windows, air from the side mirror and door handle regions will actually flow upward, over the rear fender and onto the rear decklid. There it will meet air flowing out of the roof channel, which is why the channel's widening doesn't hurt flow over the rear window. Not only is the decklid itself truncated, but the rear fender arches also end with a sharp angle, ensuring that this whole portion of the rear end avoids creating a turbulent wake as much as it can. That sharp edge runs all the way down the side of the rear bumper, less pronounced than some hybrids but still effective, so that all air flowing over the rear of the car separates as abruptly and smoothly as possible.
And it works, because the FR-S has a fantastically low drag coefficient considering how small and short the car is. Driving a Miata is like Tebow going deep with a cinder block.
I always wonder why they make hybrid cars so aerodynamic but they don't carry that over to the bread-and-butter dinojuice cars. The Sonata is a perfect example.
I personally think aero touches that you see on hybrids are cool, and a visual example of the fine balance of style and engineering. But most people couldn't care less about engineering and think a squared-off rear bumper looks stupid. These cars are hybrids, so awkward styling is perfectly acceptable. Out of necessity, we'll probably be seeing these styling cues become more mainstream, even moreso than on the FR-S.
