Here is the full list of all 38 Meow Motors achievements.
Win a race by playing for each character (career mode only)
Win a race by driving each car (career mode only)
Win all Circuit Races on 3 stars
Defeat the main villain
Earn all stars of all events
Complete all races of Revenge of Fire event
Win all Drift races on 3 stars
Win all Strike races on 3 stars
Hit 3 opponents by Shampoo during one race (career mode only)
Complete all races of Pumpkin Tour event
Hypnotize 20 opponents (career mode only)
Use Booster right on a ramp (career mode only)
Complete all races of Waterfall Hills event
Hit 10 opponents by Gum Gum (career mode only)
Complete all races of Golden Season event
Earn 25 stars of Drift races
Ears 25 stars for Strike races
Earn 15000 points for one drift race (career mode only)
Complete all races of Sea Battle event
Hit 15 opponents by Destroyer (career mode only)
Earn 30 stars for Circuit races
Destroy 15 cars of your opponents in Strike Mode (career mode only)
Hit 50 opponents by Nuts (career mode only)
Freeze twenty opponents by using Freeze Ray (career mode only)
Complete all races of Frozen Way event
Win a Circuit Race on a damaged car
Complete all races of The Tree House event
Fix your car when the only one healt point remains
Defend of Shark by using Shield (career mode only)
Hit 3 opponents by Shark during one race (career mode only)
Complete all races of Skull Island event
Get 10x multiplier at Drift race (career mode only)
Win a Drift race and don't touch the mines (career mode only)
Complete all races of West Fest event
Shock three opponents by one Impulse (career mode only)
Eliminate an opponent by hit his car (career mode only)
Complete the training mission
Keep the best RPM