Passenger Kayleigh Grant, who egged him on, has also been sentenced to four years in prison after being found guilty of abetting causing death by dangerous driving, following a five-day trial in March.
The 37-year-old, of Brightling Avenue, Hastings, East Sussex, was also found guilty of cruelty to a person under 16.
Her four children, all 13 or under, were in the back of the car. A six-year-old child was in the footwell behind Grant, police said.
Grant left the scene with her children before the police arrived and lied when questioned about the number of children in the back of the car. a police spokesperson said.
Whelan, who had only bought the car four days before the crash, messaged a friend to say: “It’s a fast, fast, fast, fast car.”
Judge David Aubrey said Whelan had been driving at “grossly excessive speed”, while Grant was “exhilarated” by his behaviour and urged him to continue to drive in that manner.