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Old 01-27-2015, 05:07 AM
  #1637  
howardcano
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Originally Posted by Slapmaster6000
For a couple of decades I subscribed to the idea that the front of the pod lifted under acceleration. I visualized the the motor pinion wanting to crawl up the spur. If you look at that, it's easy to see and think that. There's a little more to it. You are accelerating a car so fast with a force point coming from the axle centerline which happens to be above the pivot ball at the front of the pod. That acceleration force at the axle is greater then the effect of the pinion wanting to crawl up the spur, therefore the pod collapses under hard acceleration. This why the car, with too soft of a center spring, will bottom out and veer into a corner with relatively good grip track.
Brian, have you experimented with changing the anti-squat? The height of the pivot balls determines this.

Viewing from the side of the car, imagine a line going from ground level directly below the axle on the center line of the car (between the two rear tire contact patches) through the center pivot ball. If that line passes below the CG, then the car will squat under acceleration. Raising the center pivot ball will reduce the squat. Unfortunately all the other pivot balls would need to be raised the same amount (on a car with the "normal" link rear), which raises the rear roll center, and this might be more detrimental to handling than any gains from adding anti-squat.

Of course, there are also inertial effects happening as the motor spools up, and that isn't affected by the anti-squat. I'd guess that is pretty significant.
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