But it brings to mind an aero issue I don't fully understand. Modern cars often have a 1"-or-so splitter coming down from the underbody ahead of each tire. I assume it's a kind of spoiler, and that it helps in reducing drag in that region. How it accomplishes this I don't know. They might be at an angle, deflecting air out from under the car?
I've seen those, too. My take on them is:
a) it's like a lower air dam, keeps more of the tire away from the incoming air, but it's further back, where the semi-aware/barely aware drivers aren't going to jam it into a concrete parking log or curb, as they have been since the 80's
2) and it guides the air under the car, which nowadays is a fairly smooth and controlled zone of smooth ariflow, which sure beats:
iii - the other side of the tire, which is an aero nightmare by comparison.
I'm gearing up (mentally and tool-wise) to build air dams for mpg on a 90's design SUV (one designed as if it would never leave a logging road or go over 30 mph) and a 2000's era Ford Econoline. The small factory air dam on the E-150 stops just short of the inside edges of the tires, and I'm not sure why. My guess is that the front face of a tire assaulting the wind is not a keen aero strategy, but they also are concerned about the tire being able to climb a curb in city use or a minor rock or tree in logging road use.
So I've been looking at a lot of late model SUV's and pickup trucks that have airdams geared towards better mpg, and I'm seeing that some still stop short ... and some go all the way to the edge to guide air to the outside of the tire.
Speaking of aero, I recently snagged a copy of this book:
Race Car Aerodynamics, by Joseph Katz
https://www.amazon.com/dp/B004X4OIV6/?tag=atomicindus08-20
And, well, it's got some good basics here and there but it really is focused on
race cars. Not funky things designed by the firm's founder's stylist grandson 15 years before street cars even saw wind tunnels (ahem) or all of the other compromised things most of us are usually buidling aero crutches for.
And say, while you drive around with your motor from a 964, have, ponder what you can learn from a Porsche... 64.
https://en.wikipedia.org/wiki/Porsche_64
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