However seems appropriate at the time. Based just on what's in your post, I'd think this: If a glancing hit is 3-harm, I'd say a high-speed square on hit is 4-harm. Even though its generally ap, another vehicle can survive it much better. The armor soaks up some damage, the vehicle takes some and some may blow through from the sudden stop. Who wears seat belts, after all? The Driver's car is going to take the same amount in return, though, since its also hitting a car.