RUMOR MILL - NHRA PRO STOCK CHANGING AGAIN? has confirmed with a sourece close to the situation that NHRA's Pro Stock cars will indeed go through another significant change in 2019. We are told next year will usher in the Mountain Motor Pro Stock cars into the 500-inch arena. Both combinations will run in the same class with the Mountain Motor Cars having the option of carburetors or electronic fuel injection. We are told an announcement could come either in the days leading into the NHRA U.S. Nationals or during the event.