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Well back from the grave........... here is the reply from the company that is going to build the sway bars (for those that are potentially interested in some)
"The individual that is saying that you have no clue about chassis design
needs a little education himself, if he wants to come off as a professional,
but his language would need help also.
He is correct in that a flat cornering car transfers less load to the
outside tires, but that transfer is what you DON'T want. Like many amateurs,
he is confusing grip (adhesion) with drift (rolling tire distortion). In any
case a low CG car like a viper would transfer very little extra load due to
body roll anyway (with a CG of 12", and a track of 60", a 5 degree body roll
would only transfer 3.5% of its weight or say 105 lbs on a 3000 lb car or
52.5 lbs to each tire which would only be 7% of the tire's static load). A
far greater transfer is caused by the simple fact that centrifugal force is
causing the center of mass of the car to act at an angle instead of straight
down. When that that mass vector passes the tire adhesion patch the, car
flips.
He is correct also in his statement that a car with no suspension still
transfers load, but he wrongly believes that transferring load is good for
cornering. This is because he does not understand that tire drift INCREASES
with tire load, which of course causes over or under steer or, in a well
balanced car, a larger cornering radius than what is being steered, while
what he calls "grip" or adhesion would only increase if the total weight of
the car increased, which it does not as transferred weight just comes off
the two inner tires. If he had taken Race car dynamics 101, he would have
been shown the experiment that drags a brick on it's side, then on it's end,
then on it's edge and it takes the same force to pull it: As the friction
increases with the area, it decreases with the pressure, thus the force
required remains the same. Thus the transfer of weight will not effect total
adhesion.
What it does do though, is to increase the outer tire drift. As the drift
increases, the inner tires have less weight on them and are forced to drift
and or be dragged sideways as they roll. Where he says "swaybars are only
good for dialing out grip" he is again confusing grip (adhesion) with drift.
A swaybar puts more body roll transfer on that end of the car and thus
increases the DRIFT while it reduces the drift on the other end of the car
as it is suppressing body roll that would have caused more drift there
through body roll transfer via the springs or swaybar on that end. That is
why a swaybar, even a light one of say 100lbs/in, can tune a chassis so
well, as what it takes off one end it puts on the other without the
degradation of adhesion that would result from stiffer springs. Sway bars
only use body roll to effect tire loading, not car weight or centrifugal
force.
There is a reason that since Ferdinand Porsche first used them in 1930, all
manufacturers have used them to balance and stabilize their cars.
As to his comments about "poly" bushings, they do not bind on accurately
made bars that have a true axis, unless they are the incorrect size or are
in the incorrect bracket that squeezes them out of shape. Hiem joints work
fine but wear out quick unless lined.
I have always noticed that the flippant wise-guy types are that way so as to
cover up a lack of knowledge."
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