[lunarhighway]

alright...that's true, there's no connection between the dimentions and the Cd of something, just like i think it's not a good idea to generalize about hight reduction and Cd reduction. a lot of these numbers that get bounced around on the web seen to be lifted from studies made on a particular car, thats sometimes not even mentioned. and while these figures may apply to a comparable car, they sure don't apply to all cars.

i think reducing height might work well for cars with a very messy underside... proximity to the road might eliminate turbulence to some extend... or creates certain pressure effects which are favorable.

if the bottom you a car is virtually as aerodynamic and smooth as the top, this won't crate to much additional turbulence and allowing more air under the car will produce less drag than forcing the same volume of air to travel over and around the car, wich is a longer path and thus would take more energy