In my opinion, it's really not worth the work getting a cylinder of nitrogen set up in your trailer. You'd have to get a high pressure cylinder and a regulator to be able to use it. I don't know what the laws are about transporting a high pressure cylinder in a trailer, but it might be worth looking into. I can see where the roundy round racers would benefit from using it by maintaining the same pressure for possibly hours. On our car we air up a little high in the pits and make our final adjustments in the staging lanes right before we get get called to run. We also have a portable air pump that looks like a cordless drill in case we don't get the pressure right. Now I'm talking rear tires only since the fronts aren't as susceptible to the heat. Don't get caught up in the "trick of the day" mentality. Unless your working on multiple cars at the track and want to eliminate one more variable, stick with the tried an true.