Hyper miler cars will duct tape, or something similar anything that is a crevice in the sheet metal, front grill etc. to make the car more aerodynamic. The new HF or HX civic has the same motor as the base model civic, but has under body aerodynamics, and more aerodynamic wheels. More aerodynamic = less spots for air to slip around and cause turbulence.
So, while it may appear somewhat gimmicky, *it is* doing what any other car that wants to be efficient at speed does. Think of salt flat top speed cars, they remove any type of gap to streamline airflow.
My first thought when I saw this was that the reduced airflow would have more negative effects than positive... I guess at highway speeds it wouldn't be as crucial though? Still, that's when the most air would be coming in obviously... seems like it wouldn't be worth the trade-off to me, but I guess it's all about marketing, right...? :squint:
Well, think about it, only the radiator needs air passing over it, and plenty comes in from up under the front bumper. And at highway speed, constant cruising, the engine has the throttle barely open, and fairly low revs, this is the sweet spot for an engine, low load, really just maintaining the speed.
They are meant to be people movers, this is just an automobile doing what it is meant to do. Honda isn't far behind that, the tsx has a front under body cladding to perform a similar function.