Nascar pit crew opinion  

(Info on the 3 minute clock at Reading):

The first caution flag in the feature resulted in a red flag condition.  Crews had 3 minutes to make any changes to the cars. As long as they completed the work within those 3 minutes, you kept your running position from when the caution came out.  Back then, the cars were weighed before the feature.  You'd be amazed at how many tires were changed under the red. Heard rumors lots of water, concrete powder and other things inside the tires to make the cars heavier going over the scale.  Some cars 100 lbs lighter after the red.  The good old days!!!