the video below, a making of with a couple short interviews with the lead actors, does work, just press play on the arrow symbol

Phil Neilson, the second unit director, in charge of pulling off Bekmambetov's vision for the scene, tells USA TODAY that planning took six months before the lengthy shooting process. "135 hours of race footage. My original cut was 20 minutes of non-stop insanity whittled down to eight minutes,"

Unexpectedly, the actors on the chariots had to deal with lots of horse spit, froth, and farts

https://www.usatoday.com/story/life/movies/2016/11/29/ben-hur-chariot-riding-stars-dealt-real-dangers-horse-gas/94603278/