Video of 73 mph pass
The rear springs are much too soft for the extra weight of the massive motor and batteries. Stiffer springs are necessary to maintain a good rear ride height. Under acceleration the back end would squat and the positive angle of the chassis would direct all the airflow underneath the car. This caused lift and I had a blow over. I tried to minimize the up-travel of the rear shocks with spacers, but then the rear shocks would rest on the spacers and that rendered the suspension useless since there was no upward suspension travel. I also need to decrease downforce on the rear of the car. I need to trim or get rid of the rear wing. As far as I can tell the damage to the X3 is superficial. The body and front right wheel seemed to absorb most of the impact.
Overall, I am very happy with how testing went today (except for the blow over). The X3 felt very stable and very easy to drive. Acceleration was excellent. I didn't push the X3 to its limits because the spur and pinion gears are wearing themselves out very fast. I need to get a new set after the next couple runs.
I will make a couple of changes and I will be back testing soon.