It really isn't that common. If you have a valve train problem which short obviously did you can pull the plug to kill that cylinder. Short wins on the slick tracks with 8 all the time no one wants to run on 7 this can also be hard on an engine only running on 7 they have 8 for a reason and need to work in sync for everything to function properly. At paragon I can anticipate a lot of engine problems with mostly low dollar teams that can't afford the high dollar engines of some teams. I'm sure Brady would of rather had 8 cylinders but was still able to pull out the win, maybe that's his secret traction control everyone always talks about.