The Air-Benders

A look inside the Aerodynamics Department, where Lexus engineers are reviving an intriguing—and effective—Formula One technology.

Forty years ago, Formula One authorities banned “ground-effect” cars, because they were too good.

Essentially, designers figured out that any aerodynamics features that helped hold a car tightly to the road—otherwise known as creating “downforce”—were as important as designing the cars to simply cut through the air, since more road grip translates to more responsive handling.

Koshi Yamada, Project Manager of the Aerodynamics Department, knows all about ground effect, because he has deep experience in both motorsports and aerodynamics. For the last few years, he’s been using all this know-how to produce a ground-effect package for Lexus vehicles—and his ideas are working in a big way.

We’re standing, at the moment, underneath a special research-and-development Lexus GS, which has a special beauty of its own. Alongside Lexus’ current production-model aerodynamic features are some interesting additions.

Ahead of the front axle are affixed two molded plates, each with a single fin. Further back on the floor pan is a single central plate with three fins. At the back of the floor pan, immediately ahead of the rear valance, is a two-fin plate.

These fins, Yamada tells me, streamline the airflow under the car, boosting grip—or downforce, and reducing wind noise—but that’s only half the story.

Yamada’s department is also working to combine ground-effect features like these with what he calls “above ground” fins that will inform the design of Lexus rear indicator and door mirror assemblies from now on. Combined with a ground-effect package, these visible fins create what Yamada’s team calls an “autodynamic” package that will reset Lexus drivers’ handling expectations. (Side note: potential new technologies like these are rigorously tested for a year, at minimum, before being added to a model.)

“The underside of the car offers the best potential for aero improvement because it’s a large area,” says Yamada. “But the final setup [we’re developing] is a balance between an under-floor package and visible rear fins. The rear fins create the same kind of energy as a whirlwind, accelerating the air speed by around 20 percent at the back of the car and pulling the air in tightly to the sides. That helps the car have a solid feel.”

More downforce. Rear control. Enhanced handling. Little fins? Hmmm.

We move out to the nearby Lexus Higashi-Fuji test track, nestled in the shadow of Mount Fuji, where there’s a black GS F SPORT—one of the first production Lexus cars to benefit from Yamada’s ideas: it has the rear-indicator fins.

“Our aero improvements work from as little as 20 miles per hour,” he says with a smile. “You should try it.”

And so I do. I assume I’ll get to drive the GS F SPORT, but Yamada had a more dramatic demonstration in mind, using nothing more glamorous than my rental minivan—not exactly the best-handling vehicle I’ve ever driven.

From his pocket Yamada produces a handful of prototype resin fins that he attaches to the minivan’s rear indicators and door mirrors. Two minutes later, after a slow test drive around a car park to make final adjustments, he tosses the keys back to me. “Try it now,” he says.

It would be an exaggeration to say the minivan was transformed into a ground-hugging supercar, but I have to say I was astonished. The minivan was noticeably more planted on the road, even at low speeds. There was also a pleasing extra meatiness to the steering. From such simple modifications, the difference really was eye opening.

If Yamada’s demonstration is a true indication of the dynamic gains that are coming down the pike, then this Lexus commitment to air management could be one of the most significant advances in automotive design’s recent history.

However, the long-term influence it could have on future Lexus cars is an even more exciting prospect.