Pacecar Posted January 26, 2015 Report Share Posted January 26, 2015 For years, racers have known to use dry nitrogen in their race tires so that the tire pressure increase with tire temperature is lower and more predictable (vs. tires with compressed air). And racers have known that filling their tires from their air compressor on a hot moist day is a recipe for the tires to build up too much pressure on a long green flag run. Eliminating moisture from the air (which is really steam in the air) is very important to predicable and consistent tire pressure changes. When mounting tires on the wheels, it's important to mount them without using water-based lubricants, otherwise you've just introduced moisture inside the tire. And some racers go to extremes to purge their tires up to 4 times with dry nitrogen, to remove as much of the wet air that was inside the tire when it was mounted. Racers know how to bend the rules. If my quarterback wanted legally-checked low pressure footballs, I would take a small compressor into the sauna room and fill the footballs to 12.6 to 12.8 psig with very wet, warm steamy air. Then keep the footballs around 90 degF until it was time to have them pressure-checked by the referee. As the balls cooled down, they would lose pressure. And some of the humidity inside the football could start condensing into tiny water droplets, thus dropping the pressure even more as the temperatures cooled down. I could easily give my quarterback/receivers what they wanted. The "ideal gas law" that the scientists are touting predicts a pressure loss of about 1 to 1.2 psi with the cooler temperatures (depending on the temperature range). But very humid moist air doesn't behave like an "ideal gas" or inert gas, such as dry nitrogen. With super-moist air, you can get your 2 psi loss with cooler ambient temperatures. It's time for the football folks to catch up on racer technology, and start using purged, dry nitrogen in their footballs, and have the official pressure set/checked after the football has stabilized for a couple of hours in a temperature controlled room (for example 70 degF) ..... about the time Nick takes his official nap (with one eye open) in the control room before he gets to see the SuperBowl game for free. Link to comment Share on other sites More sharing options...
NickHolt Posted January 26, 2015 Report Share Posted January 26, 2015 Someone found my seminar notes! LOL Link to comment Share on other sites More sharing options...
HiTech Posted January 26, 2015 Report Share Posted January 26, 2015 THIS is so true ..anyone ever notice you lose at least 5 lbs of air pressure in your car or truck going from hot summer to winter .... tpms sensors light up your thingy on the dash and you go oh me o my i must have a leaking tire need to find the reason only to find all four tires have lost equal amounts of air .my customers scratch their heads in wonder why this happens on their cars .. my wifes new car and my jeep lost that much end of summer ...lucky for most of this winter the weather has stayed cool other wise you would, could be chasing that dang light all the time ..going from cold to summer you need to check your tires as well they can be over inflated .... someone somewhere just learned some thing today .......GREAT THREAD PACECAR Link to comment Share on other sites More sharing options...
MUmscheid 51 Posted January 29, 2015 Report Share Posted January 29, 2015 I prefer using helium. Makes the car float off into the corner nicely. Plus makes you talk funny while purging the tires... Link to comment Share on other sites More sharing options...
NickHolt Posted January 29, 2015 Report Share Posted January 29, 2015 Speaking of helium filled footballs, Michael, I'm surprised the NFL hasn't come knocking on my door. You probably have noticed that just before those last-second "Hail Mary" plays, the ball boy makes sure that a certain ball - a ball filled with Nick's famous Lighter than Air methane, which is the key ingredient in all genuine LTA products - makes it into the quarterback's hands. We've seen certain quarterbacks throw the entire length of the field using one of my "special" LTA footballs. Nick Link to comment Share on other sites More sharing options...
rickracer Posted January 29, 2015 Report Share Posted January 29, 2015 Hence! The term "Bomb" Link to comment Share on other sites More sharing options...
PAPosse Posted January 31, 2015 Report Share Posted January 31, 2015 The NFL has designed a special trophy in the event the Patriots win on Sunday. Link to comment Share on other sites More sharing options...
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