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Old 05-01-2020, 09:01 PM   #8 (permalink)
JulianEdgar
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Quote:
Originally Posted by JulianEdgar View Post

Rear wing angle
Some scatter in measurements around plus/minus 10 degrees wing reference angle, but the line of best fit shows an 8 per cent increase in car drag from a wing angle of plus 10 degrees to minus 10 degrees. That seems too much for the wing alone so I assume it is also influencing the wake and/or action of the diffuser.
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.
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