Check out rewards here.
Who is playing the race event for the first time should read this.
In this race waiting times start at lap 2, node 4.
Check out pools and waiting times proper. Sometimes you can not collect all items in 2 turns.
On browser version (PC or Puffin) arena fights count for pvp items.
Good luck.
Edit:
Finish lap 5 in less than 8 hours = reward x 10
Finish lap 7 in less than 8 hours and 33 minutes = reward x 8
Finish lap 10 in less than 15 hours = reward x10
Finish lap 12 in less than 8 hours and 30 minutes = reward x 8
Finish lap 15 in less than 17 hours = reward x 10
Finish lap 18 in less than 12 hours and 30 minutes = reward x 8
Finish lap 20 in less than 12 hours and 30 minutes = reward x 4