Edit for update 31/01/2019:
Last requirements are 10000 laps, but since the update of January 31 2019, it now 1000 laps.
When all others achievements are unlock of course.
Go solo, fever of speed (for all bonus are nitro), 20 laps,1 IA, bonus on, help boost off, destructible car off, engine wild and difficulty fatal (max). In my opinion, best car for this is the car gift when you hit level 30, the Nyvoss Spectre XI.
For the track, speedbowl or nightbowl are perfect (same track but on day or night)
With this car, this track, nitro in perfect time, good trajectory, and drive on all green accelarators, you can finish 20 laps for 7-8 mns (my best was 7mns 06 sec, and best lap was 20.337)Info
:Once campaign was finished, I had 1060 laps
Hope this help
Sorry for my english, i’m french