The Term Center of pressure refers to the Point at which all aerodynamic
forces take place on an airfoil... It Moves with changes in speed as there
is a change in aerodynamic Properties of air flow over the car....
Someone started to talk about Center of Gravity and the two types of Roll
charatarisics.... Static and Dynamic...in relation to CG...
Picture a standard Kitchen chair.. if you balance it on two legs so that it
stays upright... the center of Gravity is dead over the point at which it
is being Balanced.. if you tilt it fore or aft... it will fall over.. as a
result of the Center of Gravity being placed outside the point at which it
is balanced... this is called Static Rollover
On a Car you have four wheels and a very Low CG to get the weight outside
of the point it is being balanced on is really tough to do.... Right up
till you consider the second kind of Rollover which is Dynamic... and it
has to do with the Rolling Moments being aided by the dynamics of weight
being shifted as the car spins.... Picture our chair again only this time
take the front Legs and place them closer to the floor and give it a
shove.. the weight is forward of the pivot point but the inertia of the
shove and stored energy in the mass will cause the chair to go over
backwards if pushed hard enough... that is dynamic Rollover..
To relate this to a Car... think about the Long Slides Tom was talking
about and then think about what happens when a wheel digs into the salt...
causing the car to start to pivot about that Point.... Kinda like our back
chair legs... if the shove is hard enough the car will start to roll ....
If your not confused enough let me know.. I can be really confusing....
Keith Turk
Austin Healey 100 / Bugeye / Box Sprite / Bonneville Land Speed Racer
Camaro ( D Gas Altered )
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