Drag coefficient

[G-lancer]

I'm not sure this question is appropriate for this forum, i hope it is. (new here) -

How come cars like lotus omega carlton which looks very cubic has low Cd like 0.28 and cars whom looks so aerodynamic like lamborghini countach has bad drag coefficient like 0.40+ ?

what am i missing?

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[imported_fao]

:roll: I don´t know, maybe because the countach produces too much turbulence on its back. Interesting question.

[Manager]

First of all, sorry my bad english! The drag coefficient is directly

related with drag force. What cause this drag force? Not only the object shape (a car in this case) but also the surface (that's why the golf balls have those cavities. Whitout those cavities the drag force will be bigger). In our case: Lotus Omega is bigger than Countach, but the Lamborghini's body is all made of plane plates. The Countach body will create very turbulence, not only in the back, but all over the car. I hope that you understand the idea.

[thepolarfoxqx]

The issue with drag is this: When you go fast, you need more aerodynamic downforce to keep the car planted on the ground. Unfortuneately, when you make more downforce, you often make more drag. Also, car manufacturers are getting better and better at making the shapes of their cars more aerodynamically efficent. When Countach was designed, the science of automotive aerodynamics was not as advanced as it is now.

[G-lancer]

I'm not sure i understand why the golf ball is faster through the air when its not smooth, but now i understand a little better why the Countach has such high drag coefficient.

Is it safe to say that the big rear spoiler on mark1 Impreza turbo was more about reducing turbulence at the rear than to make downforce?

[thepolarfoxqx]

i am pretty sure that is about downforce. usually you remove things like that to remove turbulance. a ferrari 360 has a very low drag coefficent, and it has no spoilers or air-dams. a countach is a wide car with alot of facets. a golf ball flies further with the dimples due to an aerodynamic pheonomenon. The dimples create pressure pockets of air - which lead to lift being created - and holding the ball in the air better.