| I posted that. What I learned: you can't alter the ultimate load transfer with spring rates; that's primarily a function of the physical dimensions of the car and the torque of the engine. I previously had some notion that a car squatting on its rear tires would be placing a greater load on them than a car that was level. Not true, except for a small, insignificant transfer that might come from the squatting motion raising the center of gravity a little bit. Anti-squat is a sort of mechanical bind, created by angling the horizontal planes of the control arms, that counteracts the squatting motion and 'pushes up' on the rear tires. It's expressed in a percentage... I'm pretty sure 100% anti-squat would keep the car level under hard acceleration. An all out drag car might have an anti-squat of like 160%, so the back end actually rises when power is delivered. The push-up anology you gave is a good example. When the anti-squat force pushes the body up, the reaction force pushes down the tires on the road. Just like in a push-up where your arms move your body up but force your hands down on the ground. But no road car will ever have 160% anti-squat...in fact I'm pretty sure IRS is limited to around 25%. So the effects aren't going to be that dramatic. I do remember reading posts saying the Z seemed to have a lot of anti-squat built in, but I've never seen any technical data to back that up. Also, the degree of squat or anti-squat is only going to effect rear traction during the transition from level (at rest) to whatever the equilibrium squat height is. This is the same concept as in the pushup; your hands will deliver the same amount of force to the floor when you're at rest at the bottom of the pushup as when you're at the top of the pushup, at rest. Only when you're transitioning up or down will the force change. So we're only talking about a small time interval where the suspension geometry can make a difference. But I guess that's an important interval. Also learned that when a car is under the anti-squat ''binding'' the effective spring rates can soar, making the rear suspension particularly sensitive to irregularities on the road, making traction difficult on all but the smoothest surfaces. I kind of doubt that there's enough A.S. built into the Z to cause that, but then again... maybe there's more to the skittery rear-end behavior on hard launches than overly-compliant rear suspension/subframe bushings. Well, I just wanted to share this knowledge, and to verify it possibly. It's probably going to raise more questions than it answers, at least for Haken, but hey, it's interesting to me. Thanks for your comments, and any more input/comments would be appreciated.
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