16 cars on a 7×8 lot. 50 seconds on the clock.
16 cars left
You have 50 seconds, starting at your first tap. A bump costs 3 seconds.
Drive the cars out in this order: 1, 2, 3, 4, 6, 7, 9, 10, 11, 12, 5, 8, 13, 14, 15, 16.