Aerodynamic details from the Chicago Auto Show (picture heavy)
 

It's that time of year once again; after spending the afternoon at the Chicago Auto Show yesterday, here's the state of aerodynamic devices for the 2018 model year.

Grill Blocks

Grill blocks are becoming common, and there is now the potential for owners of some cars to install a factory-blocked grill from a related submodel. Example: the BMW 750 has open kidney grills, while the 740 has completely blocked grills. The Buick Regal TourX, essentially a Regal wagon, uses an interesting, partially blocked upper grill:

http://ecomodder.com/forum/member-vm...219-144516.jpg

Ioniq hybrid owners could swap in the grill from the Ioniq EV, which is a thing of beauty:

http://ecomodder.com/forum/member-vm...219-164437.jpg

The regular Ioniq, which I had looked at in Indianapolis last month, has what appears to be a completely blocked grill as well; closer inspection showed that there are actually two moveable slats on either side of the emblem.

http://ecomodder.com/forum/member-vm...219-171212.jpg

Pretty slick; most manufacturers just put the shutters behind an open grill. The only other OEM I've seen with visible moveable slats is Mercedes.

Wheels

Low-drag wheel designs continue their two-tone crusade, likely in the name of consumer acceptance. Some of the standouts were, again, the Ioniq:

http://ecomodder.com/forum/member-vm...219-171153.jpg

...and Sonata plug-in:

http://ecomodder.com/forum/member-vm...219-165240.jpg

Runner-up: the Insight protoype:

http://ecomodder.com/forum/member-vm...219-163457.jpg

Air Curtains

The indisputable winner of the air curtain game is Hyundai. Every single one of their models--sedan, hatchback, CUV, or SUV, from the $15,000 Accent on up--has front wheel air curtains.

http://ecomodder.com/forum/member-vm...219-164612.jpg

Two full-size trucks now use them, the Ford F-150 and 2019 Chevrolet Silverado. The Ford is the only vehicle to use a horizontal inlet:

http://ecomodder.com/forum/member-vm...219-150640.jpg

The Silverado's curtains are HUGE. Sorry, no pictures--it was on a rotating dais behind a glass partition, so I couldn't get close enough.

One of the few manufacturers to not use air curtains at all is, surprisingly, Toyota.

Acura's booth had a couple of race cars. Their LMP car had this interesting variation on the air curtain ahead of the rear wheel:

http://ecomodder.com/forum/member-vm...219-150231.jpg

Also note the annular ring on that wheel face.

Wheel Air Dams

Wheel air dams are now ubiquitous, but still with wide variety in size, shape, and placement. The Toyota Corolla, one of the older designs here, still has a previous-generation style air dam, straight across and with an inboard cutout:

http://ecomodder.com/forum/member-vm...219-153527.jpg

Most cars now have at least some curvature in the air dam, like this one on the 2018 Prius Two:

http://ecomodder.com/forum/member-vm...219-152556.jpg

Air dams varied from the absurdly small (Mercedes S550):

http://ecomodder.com/forum/member-vm...219-160427.jpg

...to quite large examples, such as the Cadillac CT6:

http://ecomodder.com/forum/member-vm...219-145345.jpg

Some have cutouts (2018 Honda Accord):

http://ecomodder.com/forum/member-vm...219-162505.jpg

But most are solid, made of rubber or plastic.

Front and rear, a few cars had plastic or rubber fairings in addition to the dams. Porsche 911 Carrera:

http://ecomodder.com/forum/member-vm...219-144710.jpg

The Ford C-Max Energi has quite large rear fairings; I've ordered a set and will be adding them to my Prius, in addition to modifying the front air dam design to extend downward and curve around the wheel opening.

Some cars had no wheel air dams at all. 2018 Camry:

http://ecomodder.com/forum/member-vm...219-153200.jpg

The only pickup manufacturer using rear air dams is GM/Chevrolet, which has quite prominent dams on both the Colorado and Silverado/Sierra:

http://ecomodder.com/forum/member-vm...219-180316.jpg

Underbody

Speaking of pickups, none have underbody paneling. Instead, all the trucks I looked at have prominent air dams. 2019 Ram 1500:

http://ecomodder.com/forum/member-vm...219-161109.jpg

I checked all 4 of them at the show, and none had the lower-able dam.

Very few cars had front air dams, with some notable exceptions. The Audi S5 and TT had interesting partial dams:

http://ecomodder.com/forum/member-vm...219-155828.jpg

http://ecomodder.com/forum/member-vm...219-155921.jpg

Some GM cars still have air dams, like the Cruze hatchback:

http://ecomodder.com/forum/member-vm...219-163726.jpg

At the rear, most cars now also have fairings. Here's the Mercedes S550 again:

http://ecomodder.com/forum/member-vm...219-160320.jpg

Toyota's vehicles all have vanes for stability. 2018 Sienna:

http://ecomodder.com/forum/member-vm...219-153435.jpg

But, the winner for best underbody treatment is...surprise! The 2018 Chrysler Pacifica Hybrid had by far the smoothest underside:

http://ecomodder.com/forum/member-vm...219-161607.jpg

Air intakes

I made a point of checking out the 2018 Mirage's "cold air" intake. Turns out it's just a pipe sticking forward in the engine bay:

http://ecomodder.com/forum/member-vm...219-175854.jpg

The 2018 Prius and Prius Prime had what looked like an intake routed to take in air before the radiator. Closer inspection revealed that it is, in fact, completely blocked inside and taking in warm engine bay air:

http://ecomodder.com/forum/member-vm...219-151701.jpg

I'm not sure why it's routed to that spot. The hood is sealed there with a rubber gasket, so it's not taking in cold air.

Other odds and ends:

http://ecomodder.com/forum/member-vm...219-152100.jpg
Toyota Prius Prime spoiler and rear glass

http://ecomodder.com/forum/member-vm...219-144904.jpg
Porsche Panamera rear fairing

http://ecomodder.com/forum/member-vm...219-150205.jpg
Acura LMP car rear wheel pressure relief

http://ecomodder.com/forum/member-vm...219-165743.jpg
Hyundai Ioniq EV tail lights

Looks like they had a nice clean floor to roll around on. :thumbup:

Ford parts on a Prius? Pix or it hasn't happened.

Dang li'l thumbnails so hard to see.

Heat recovery seems to be quite critical in Toyota hybrids, plus since a little amount of air/fuel mixture will always return to the intake manifold during the compression stroke. Then, adding up some heat is likely to prevent it from condensing :D

Awesome evaluation! Thanks for the roundup.

Very odd on the Mirage intake. In 2017 Mitsubishi specifically added a guide type piece of plastic to 'improve fuel economy' that made it suck in cooler air. Here is a picture showing the part. Its odd that it is absent on the 2018 model.

http://mirageforum.com/imgs/2017update01.jpg

Fantastic thread, photos and captions VMAN455.

I think it makes for a strong argument that aerodynamics is no longer considered a nuisance, it is a necessity.

Keeping in mind that every dollar saved is a million dollars in profit (someone claimed in the forum earlier), and that every item added adds weight (and weight is the enemy) - then all these pans and aero-tabs fought for their right to exist though a very caustic political process within their respective companies - and won.

This is indeed an aerodynamic evolution.

Mostly seen by getting on your back and snapping a picture.

When aerodynamics is allowed to rise off it's back, then it will have gone up the food chain. Right now aerodynamics is best appreciated by snakes and worms crawling on their belly. :D

The luxury brands (Porsche, Mercedes, Jaguar) had nice, plush carpets.

The fairings are supposed to ship out today or tomorrow. I'll stick them on when I have the car jacked up for its oil change in a few weeks or so.

All 4 were like that. As I was walking through, opening the hood on each Mirage, an attendant was following me around wiping them down with a microfiber cloth.

Airflow management under the cars appears to have little convergence toward any sort of "ideal" like we've seen in things like backlight angles--the industry hasn't reached any consensus beyond "wheel air dams and closeout panels work"--but how big, how much coverage, placement, all vary widely.

A new thing this year is some sort of fibrous covering on closeout panels; I wonder if this is for noise reduction, as the resonance of the (thin) plastic panels is damped significantly.

And, as usual, I was the only person looking under cars. An attendant at the Mercedes booth said, after seeing me take a picture of the front wheel air dam, "You don't need to pray; you can get the car." When I said the underside of the car was the most interesting part, he didn't seem to understand.

Apparently that intake guide on the Mirage is under the radiator support. Here is an upside down picture from a Mirage owner clarifying things for us.

http://mirageforum.com/forum/attachm...6&d=1519230919

Thread of the month!

I do it! It'd be fun to go to a car show with you, Vman455.

And thanks for the chuckle. Quick-witted attendant!