Supercharger displacement, the tune to go with it. Fresh air through the hood instead of inside light. The car she did that in basically has twin turbos in place of the supercharger to create positive manifold pressure. Except for the stupid speedkore carbon fiber body panels it is stock demon. The owner would have done better to leave it a stock steel body and get a slower record number. The body work muddies the water.
The Hellcat is not stock in any respect, maybe some body panels. Liberty 5 speed ( no clutch used on shifts) solid axle rear, and I'm going to guess that the brakes are not as capable as the stock brakes on a Hellcat (lighter, much lighter)