from:larrybsp@aol.com (Larry Stark)
James,
It is not the general consensus you want to totally
eliminate antidive in autocrossing. Its a beneficial characteristic. Without
antidive as soon as you hit the the brakes you are going to compress the front
springs and increase the load on the front tires. Remember the traction circle.
If
the tire is loaded from braking forces it loses turning capability. Not only
have you have used up much of your suspension travel, when you start your
turn and introduce body roll you can bottom your suspension at which point you
have no suspension and all the weight transfer load will go to that tire
causing
it to lose traction. Anti dive is usually controlled by the angle of the
upper and lower control arms relative to the ground. The upper arm is sloped
downward toward the rear and the LCA is sloped upward toward the rear.
The amount of anti dive is determined by the instant center of the
intersection of the upper and lower control arm projections. A line is drawn
from the
from the tire contact point through the instant center and continued back to a
vertical line projected from the CG. The elevation at the intersection relative
to the CG height determines the amount of anti dive. There is disagreement by
"suspension experts" as to the merit of antidive. Antidive cause changes in
caster under braking and in excess can lock up the front suspension. Almost
every factory car has anti dive. I believe in moderation, 10% to 15% anti dive
is advantageous for the points made earlier.
Larry
>
> is the general consensus that race (autocross) cars should have zero
> anti-dive?
>
> if i remove my anti-dive, what other compensation do i need to do? how will
> the car feel different?
>
> james
> OSP - Our Speedy Primadonnas
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