Not a car, but directly applicable. This uses a simple curvature on sheet metal that could easily be replicated to fair an automobile's rear wheels with garden edging or similar.
Also note the Jaray-like greenhouse, splitting air sideways at the windscreen much like an automotive front air dam.
Spartan Cruiser 1935 by
kitchener.lord, on Flickr
Oh, and an Auto Union.
Hans Stuck and Auto Union by
kitchener.lord, on Flickr