Long Duck Dong

Someone claimed to have went 200 mph on a public road in his buddies "modified" Cayenne. I had to call BS on it...
200 MPH Cayenne?? Post #27

charlieXS

highly unlikely.

Kooser

Urban Legend

wingless

My CT has no problem passing the 200 mph mark, when dropped from an airplane. It also then stops really quickly too, must be those legendry Porsche brakes (painted red, of course).

ltc

IIRC, a German tuner did produce a 200mph Cayenne...it was in a past version of Excellence or European Car...can't remember.

LVDell

It was in Excellence (May) on p133. And the article stated that their new "SUV TOP SPEED RECORD" was 192.78mph. So I would have to call BS as well.

Apparently the story embelisher over on that other board that claims the 200mph doesn't understand the concept of drap at high speed. Not to mention this record run of 192 was done in a controlled environment, not a public road. Just gotta love some of the crap that gets posted on some chat boards (ours not withstanding).

Kooser

Maybe it was a mispost and he meant to say 200Kph, which would be 125mph.

MadFox

Actually, you got my engineer brain working... what we need is the drag co-efficient of the Cayenne (assuming that we dropped it nose first and it stayed that way). And low and behold... I found it at .39 right on the PAG website! Thus. we can calculate the actual rate at what our beloved Cayenne would actually "fly" into the earth.

Terminal velocity: An object which is falling through the atmosphere is subjected to two external forces. One force is the gravitational force, expressed as the weight of the object. The other force is the air resistance, or drag of the object. The motion of any object can be described by Newton's second law of motion, force F equals mass m times acceleration a: F = m * a which can be solved for the acceleration of the object in terms of the net external force and the mass of the object: a = F / m. Weight and drag are forces which are vector quantities. The net external force F is then equal to the difference of the weight W and the drag D: F = W - D. The acceleration of a falling object then becomes: a = (W - D) / m . The magnitude of the drag is given by the drag equation. Drag D depends on a drag coefficient Cd, the atmospheric density r, the square of the air velocity V, and some reference area A of the object: D = Cd * r * V ^2 * A / 2

Drag increases with the square of the speed. So as an object falls, we quickly reach conditions where the drag becomes equal to the weight, if the weight is small. When drag is equal to weight, there is no net external force on the object and the vertical acceleration goes to zero. With no acceleration, the object falls at a constant velocity as described by Newton's first law of motion. The constant vertical velocity is called the terminal velocity. Using algebra, we can determine the value of the terminal velocity. At terminal velocity: D = W

Cd * r * V ^2 * A / 2 = W

Solving for the vertical velocity V, we obtain the equation

V = sqrt ( (2 * W) / (Cd * r * A)

Thus, let's assume NO ONE is inside the vehicle and the only "luggage" is ltc's former straight jacket and/or his TCU! The calculation for a S would be if we shoved it out of a cargo plane at 35,000 feet:

V= sqrt ((2*4949 lbs.)/(.39 * air density (fm table) * Area (front view ~ 75.9" x 66.9") A= 35.2 sq.ft.

THUS -- Actual Maximum speed of a Cayenne S is 674.1 MPH! or 988.7 ft/sec.
A Turbo is still slightly faster than a S!! 690.5 MPH or 1012.7 ft/sec