[freebeard]

Originally Posted by radioranger

Gotta point there, I guess another way is to duct air from a high pressure area to a lower one, sort of how they cooled the engines in the Shelby Daytona Coupes, cant think of any ordinary cars that do that , probably because of weather issues, I was also wondering if anyone has tried to relocate their mirrors to the door so the air can flow around the windsheild better, maybe sit the mirror out of the main air flow, maybe back a bit....

• A modern car underbody is a plenum [considered with the road surface] that mangles, or sorts and orders, the airflow from the front and sides out the rear.
  
• 1940s peep mirrors and newer buses and firetrucks with forward-reaching stalks.

Originally Posted by aerohead

Technically, it should make no difference. According to the literature, it requires very little leading edge radii on an automobile to fully 'saturate' the drag reduction. Once you've achieved attached flow there, no amount of further softening will lead to additional drag reduction.

• Cybertruck chamfers.