In the final 20 seconds of the video the motor sounds like it is hurtin.

 

If you listen to the parts where Travis is giving the engine a little gas in the last part of the video, the engine sounds like it's running normally. I wonder if he means that he was spraying nitrous + fuel after the engine hit the rev limiter ??? Because the rev limiter just cuts 99% of the fuel, and spraying just nitrous would not create any power... the idea of spraying nitrous after rev-cut kinda freaked me out.

At one time, I thought I could spray a large nitrous/fuel shot after the limiter cuts fuel and keep the engine pulling on up. This would take a LARGE combination shot, but if tuned right, it might work. I wonder if that video just showed it happening. ?? Travis??

 

If it's possible to tune it for the higher rev without meaning to, then he did it.