I was just wondering how much aerodynamics makes. Most of us know that the s2k has crappy aero, mostly because it is a convertible, with its almost straight up windshield.

If a s2000 coupe was made, same weight, same power, just much better aerodynamics, how much of a difference would it make in high speeds?

Whats the specification for how aerodynamic your car is? And is there a website that shows many different cars aerodynamics?

 

i think s2000 is aerodynamically good.

 

makes big difference in highspeeds. for best top speed is hp and aero.
theres a vid of a s2k running against a Z with the top up and down and makes a huge difference. Z always pulls on the s2k at triple digits. my guess is the aero.

 

the s2k sounds faster when you're driving it with the top down

 

For best aero,with top down,yuo need a tonneau cover.

 

Our drag coefficients are SUV high if I remember, but actual drag force is low due to our small frontal area.

 

our drag coeffient is better than most SUVs. our drag CF is somewhere in the .37-.38 area. not bad. consider cars like the coupe mustang GT is .36

 

I bet ours is much less with the HT.

 

The answer to this is a little more complicated than you might think.

Drag is proportional to the size of the object and the "dynamic pressure" (1/2 * air_density * velocity^2). This usually ends up being descibed as:

D = 1/2 * rho * V^2 * S * Cd

Where rho is air density, V is velocity, S is some reference area, and Cd is a non-dimensional number called the Coefficient of Drag. For cars, S is usually taken to be the "frontal area".

So the Cd is a measurement of how efficient the shape is, independently of the size of the vehicle. That means if we have the same Cd as an SUV, we can still have less drag because we are smaller. But if a coupe of the same size has a better Cd, then it will have less drag.

Lift (or negative lift, aka downforce) has a similar equation, except it has a Cl instead of Cd.

The ratio of Cl/Cd is one of the key measures for an airplane of "how aerodynamic" it is. For an airplane, you want Cl to be high and Cd to be low. But in the case of a street car you probably want Cl to be close to zero and Cd to just be as small as you can get it.

ps. Cd (and Cl) are not constants! They depend on another factor called Reynolds Number, which changes with speed. There are also different kinds of drag, including drag which is caused by lift. So it's only an approximation to say that the drag is a fixed number that is proportional to V^2, but it's a pretty good approximation. And them you have to factor in mechanical friction etc., so the whole thing gets complicated quickly.

 

I've always know negative lift and downforce to be two different actions.

If I recall correctly, downforce is the action of air pushing the car down. Think of the giant wing mounted at a 45