Quote:
Originally Posted by GretchenGotGrowl
Maybe I misunderstand, but it sounds like we are saying the same thing. Adding a person imparts a downward force (mass of person * acceleration of gravity) and negative lift imparts a downward force (pressure differential). Both can be expressed in terms of Newtons (1kg m/s2 = 1 Pa = 1/6,894.8 psi). Both increase grip by the same principle, but negative lift also increase drag but adding a person doesn't really (unless you strap them to the roof  ) Does that sound right? |
Yes. However, you were originally talking about straight line acceleration. And in that situation, there is a difference. For the car with the passenger, you have increased the mass by about 90 kilos (200 lbs). In the downforce car, you've probably added something between 90 and 300 newtons of drag (translating to 20-70 lbs), depending on the aerodynamic efficiency of the added aero-bits. For reference, at ~170 mph, most cars have something like 400-600 lbs of aerodynamic drag. I have no clue how much propulsive force a 2015 Z06 generates at the speed where it might be generating 200 lbs (net) of downforce. Which means I am as far as I can go with guesstimating numbers.