The front tends to nose upward due to an airfoil effect. There is also an effect due to conservation of angular momentum (page 151-152). The rear wheels are driven clockwise, which tends to rotate the rest of the car counterclockwise. Gravity pulls down on the car, providing a clockwise torque around the rear axle to fight these effects. Having a long car increases the lever arm of the gravitational force. Also, the long body gives the car a large rotational inertia around the rear axle, minimizing its angular acceleration.