When a car's chassis hits the track surface, sometimes making sparks fly. This is because the suspension has hit the maximum amount of compression it can take, for example due to increased downforce.
This is when the chassis actually touches the ground as the suspension compresses from aerodynamic downforce, and from vertical G forces on oval track banking or over bumps in the pavement.
When the front or rear suspension systems use ALL available travel to absorb an impact. Forks or shock have completely collapsed.
When your vehicle reaches the limits of the suspension travel (such as when going over bumps), and the vehicle's springs are completely compressed. The vehicle produces a transfer of noise/harshness, particularly through the steering, with possible contact of the undercarriage with the pavement.
A noise and jolt created when the compression cycle of the suspension ends at the bump stops.
F1 cars run so low to the ground, their undersides can often touch the floor or â€˜bottom out
When a car's chassis hits the track surface as it runs through a sharp compression and reaches the bottom of its suspension travel.