Phineas and Ferb - Speed Demons

Lazy summer days? Not for Phineas and Ferb. One day the duo fixes up their mom's car and takes it to the races. The next they build the world's craziest roller coaster! The neighborhood's not likely to be the same after this. But will Dr. Doofenshmirtz's plan to reverse the spin of the earth with a magnet trained at the eastern seaboard succeed and ruin things for everyone?