One important side effect of going fast is that you need to slow down fast. So better braking power. (Though the problem with supercars is that simply using som

One important side effect of going fast is that you need to slow down fast. So better braking power. (Though the problem with supercars is that simply using something that needs replacement every few hundred miles is "acceptable".) Similarly anything that rotates has to withstand torque and centrifugal force. Eg wheels. (See also this: https://www.youtube.com/watch?v=K_ImAm1WhcY https://www.youtube.com/watch?v=K_ImAm1WhcY for what it takes for going 3x faster.) These advances result in capital investment for R&D, percolate through the supply chain, and this can lead to better techniques here and there. (But I think after a certain point the disparity between the technology - the trade offs - needed for 100 mph and 300 mph become so large, that the resulting new/better capabilities doesn't mean anything for the normal automobile ecosystem.)