This was the plot of a really, really, really bad made-for-tv movie in the 80s. I only saw it once, when it aired in the 80s, and even now I remember the ludicrousness of the bus engine plot point and how bad the movie was.
Awesome 80s tv star cast, absolutely terrible movie.
Anthony Edwards was the rich bad guy, perfect hair, homecoming queen girlfriend (Nancy McKeon), student body president, starting QB, drove a 911. Michael J Fox was the working class protagonist. Various shenanigans lead up to the conclusion, a drag race between Edwards in the 911 and MJF in some crappy car, except (plot twist!) that MJF and his friends steal a bus engine and install it in the crappy car at the last second, and win the race. MJF wins the affection of the school and the pretty girl.
At the time, I had just finished rebuilding a straight 6 on our β68 Dodge 100 step side, so I understood just a little bit about how ridiculous it was to suggest that a bus diesel engine in a passenger car would work, and would automatically give the car enough power, torque, and torque applied correctly, to win a race against a 911.
https://en.m.wikipedia.org/wiki/High_School_U.S.A.