Good for a 5-minute power trip, bad for long-term enjoyment. Proceed at your own risk
If you are looking for a way to unlock every car instantly, the "Money Glitch" (often involving time manipulation) is effective but comes with significant downsides. traffic jam 3d money glitch
Passing other vehicles very closely at high speeds triggers a significant reward multiplier. Good for a 5-minute power trip, bad for long-term enjoyment