Ka-chOWW!
Ka-chOWW! is a book.
Plot
Lightning McQueen is still not used to dirt track racing, and when he begins practice with his team, he slides straight down a cliffside into a big pile of cactus.
It turns out Doc was watching his racing fail, and he keeps McQueen at the track. He continues to practice, but sometimes he makes it but sometimes he doesn't. Eventually, Lightning makes the turn perfectly and he has successfully learned how to powerslide on dirt.