Nitrogen is used at the track for the FOC/FCA events here in the north east depending on the company you run with. It helps due to the expansion of oxygen in regular air in tires. If you guys run you car on the track, take temp and pressure readings when HOT. You will see the difference.
Just to be clear, oxygen doesn't expand significantly differently from nitrogen. Both gases will expand predictably with heat. It is moisture in air (humidity) that you want to avoid... water expands tremendously with heat as it changes from liquid to gas. Thus, with a little more humidity in your tires, you'll find that your tire pressures increase much more than expected from cold to hot; and more importantly, if the moisture is different in different tires, then your handling balance will be disturbed as the tires heat up. So, for your track events, dry air is every bit as good as pure nitrogen.
Okay, we've established that it's a good idea for the track...what about the street? Does anyone use nitrogen in their street cars? Are there any discernable advantages?
If you have a real low mileage Ferrari... to where your tires, tread-wise, last for years and years... then keeping the oxygen out of them will greatly reduce the oxidation of the rubber. In that case, it is arguably an advantage. If you're going to go through your tires in less than 3 years anyway, then pure nitrogen is probably not of significant value on the street. (That 3 year number is fairly arbitrary.)
Granting the benefits of nitrogen, IMHO the great majority of track day drivers and amateur racers should concentrate on driving and set-up long before even thinking about nitrogen. My advice is that notrogen is NOT worth it for most track applications, and I'm reminded of folks in SCCA I've seen using tire warmers. It looks cool, though, and if it adds to the fun, what the heck, it can't hurt.
Okay so were is the best place to get the tires filled? Can you go to a truck stop that services big riggs, or were?
Tires must be drawn down to ZERO psia(bsolute) with a vacuum pump, not just have the core pulled out and left at atmospheric, even repeatedly won't help. As I've said before, "suck, then blow" (suck the air out, then blow the nitrogen in). And on the subject of mounting lubricant and race tires, mark the position of the wheel's valve stem at mounting time, then take a look after a track session. Hmmmm. I've seen top notch tire/ wheel combinations spin as much as 180 deg in 30 minutes. Typically at least a couple degrees, usually the fronts due to braking. Trans Am cars spin the rears occasionally. Best regards, Rob Schermerhorn
Here some opinions from the Porsche guys: http://forums.pelicanparts.com/showthread.php?s=&threadid=119524&highlight=nitrogen+tires http://forums.pelicanparts.com/showthread.php?s=&threadid=39517&highlight=nitrogen+tires http://forums.pelicanparts.com/showthread.php?s=&threadid=111346&highlight=nitrogen+tires -Wayne
