This information was posted on NHRA web site fyi
In an effort to eliminate bottlenecking, confusion and aggravation, we are implementing a new number card system at The Strip at LVMS this year for sportsman stacking. Competitors will be given a numbered card, and rigs will be brought into the pits in order based on the number on the cards. As per the Pre-Event Stacking Schedule, stacking for the Denso Spark Plug NHRA Nationals at The Strip begins at 7 a.m., Tuesday, March 29th. Racers who stack prior to the appointed time will be penalized and issued cards starting at No. 101, while those who arrive after the appointed starting time will begin with No. 1. THIS IS NON-NEGOTIABLE
