After rewatching this episode, it was strange to see Stevonnie keeping up with Kevin most of the time, but I noticed is that Kevin's car was shaking like his car was about to explode which could be due to the excessive body kits and an aftermarket spoiler, while Stevonnie's car was running smoothly for obviously been stock and likely tuned.
And at the end of the race, Kevin cheated for using nitrous and he "won", while not realizing that he possibly destroyed the engine.
I can say that Kevin is just a wannabe racer who "modified" his sports car just for attention while racing with regular drivers.
