Quote: Hey Monte, in your spare time, it'd be very interesting to test a 4 link car like this.......Put the IC on the anti-squat line, make three passes...........then take OFF the shocks and make three more passes and see what it does.........Those that claim that the IC needs to be on the anti-squat line also say that shocks don't do anything and aren't even needed on the rear because the body of the car is neither seperating or squatting.......(if the track is flat, but that's another story)..........
sorry i'm late to the party here, but i want to try and clear up some suspension misconceptions. The Instant Center of a suspension group is the point where suspension rotates around. What this means, is each type of suspension has to be evaluated differently. On a leaf spring car it is the front spring perch. On a ladder bar setup it is the front mounting point of bar. Now, on a 4 link car its an imaginary point where if you were to extend line through each suspension, it would be where the 2 intersect. Because of this you can get adjust the instant center to about anywhere you want on an adjustable 4 link. The Caltracs is a band aid fix, and in my opinion it has its uses, but because its limited adjustability its not maximizing the potential of the vehicle. Now I dont know who dug up the Anti-Squat info, Anti-squat is not a line from the CG to the contact patch, but its close to that, its a line from where the horizontal component intersects intersects a verticle line drawn through the front tire drawn through the rear contact patch. That line is 0 for anti squat, and 0 for squat. This means that the suspension will not lift the chassis, or the axle under torque. If the instant center of the suspension is above this line it has anti squat, which means it will try and lift the chassis under torque, if its below this line, it will lift the axle causing squat. Now we have to consider the dynamics of weight transfer next, when a car accelerates the horizontal compenent of G the accleration, moves the CG back so because of the different acceleration vector of gravity, its moving more weight to the rear tires, which will compress the suspension. Any time a spring moves, it must have a shock on it, because a spring will naturally want to resonate, the shock 1, controls the oscillation of the spring, and 2 also controls, the speed at which the spring and compress, and expand. So just because a car lowers in the rear doesnt necessarily mean its squatting. In the ideal launch, you want as much energy used to move the car forward, Not up, and not to move the suspension, and definiately not wasted at excess tire spin. So you have to balance the suspension to move forward as fast as it can, while still putting enough downward force on the rear tires. Anyways I wrote this quickly, and will add more later, I just wanted to clear up some suspension myths I noticed on here.
