View Single Post
Old 06-17-2020, 04:55 PM   #108 (permalink)
aerohead
Master EcoModder
 
aerohead's Avatar
 
Join Date: Jan 2008
Location: Sanger,Texas,U.S.A.
Posts: 16,320
Thanks: 24,442
Thanked 7,387 Times in 4,784 Posts
rear spoiler and front lift

Quote:
Originally Posted by JulianEdgar View Post
It is still raining, so no testing for the moment - the tape won't stick.

But I was thinking about the above situation, where wing angle seems to increase drag to a greater extent than would be expected. I think perhaps it's because the nose of the car is being lifted.

The wing is positioned behind the rear axle line, and we know it develops measurable downforce. The air suspension control system is not set to rapidly correct at speeds over 80 km/h (50 mph) and so it is likely that when the wing angle is set to provide lots of downforce, the rear suspension is being compressed and the front slightly lifted.

Of course, the beauty of on-road testing is that all factors are taken into account - the outcome is what it is.
This was found to be the case when the 1st-gen Chevy Camaro was tested at 115-mph.
Adding an airdam helped the matter.
Removing the spoiler, while maintaining the airdam was deemed the most satisfactory configuration.
The Camaro had quite a bit of rear overhang, so the downforce, acting over that moment arm was responsible for lifting the nose, exactly as you describe.
__________________
Photobucket album: http://s1271.photobucket.com/albums/jj622/aerohead2/
  Reply With Quote