Nail'd

The wooden bridge on the AERIAL highway is ideal for this task. When you fall from it, you are resurrected on it (in the middle). You push a friend at the beginning of the bridge and he is resurrected in the middle. Returns to you in reverse and repeat the operation as much as necessary.

Just don’t push (or fall yourself) off it in the middle or further than the middle, because... you will be resurrected behind the bridge and you won’t be able to go back. Only if you drive a circle, and this is a waste of time, of which you already only have 10 minutes (that’s how long the race lasts if there are no finishers).