Aerodynamics & Diverting Wind Resistance ?

pishta said
I thought the winged cars were docile at 150+? I read one report that " at 150 the wind noise went away and the car settled in nicely..." one was faster than the other, had to do with the chin spoiler and rear window shape. Myth busters did a test on open or closed tailgate for mileage, they both ran out of of gas (80-85 miles) within 5% of each other, the tailgate UP won! They said the pressure buildup in the open bed of the closed tailgate made the wind go over the truck smoother. the open tailgate didnt have the same high pressure bubble and the back of the cab acted like a parachute with a low pressure area. I see semi trucks with tail cones now.

I’m not sure on anything except the Daytona body and it’s instability over 150 MPH.

Interesting thing about the tail cones. There is a huge exit loss at the back of those trailers. The air is crashing back into the end of the trailer trying to fill up the space, which is lower pressure. That creates vortices which cause drag. It’s a great study to watch the air move around the back of those trailers. It’s a very good object lesson.

Anything you can do to put the air back together smoothly at the end of the trailer reduces drag, and therefore increases fuel mileage.