Thứ Sáu, 24 tháng 2, 2017

Nitrogen fill for tires? Track/Auto-X part 1

zoomfactor 01-09-2004 04:40 PM

Nitrogen fill for tires? Track/Auto-X
Anyone here use nitrogen for filling their tires? I just had a wonderful and insightfull coversation with an old oval racer.

He indicated that nitrogen had significant benefits for tires due to reduced moisture and resistance to pressure fluctuations (as compared with air). It was his experience that tires still heated up predictably but tire pressures remained more consistent with nitrogen.

In between (slow :rolleyes: ) Auto-X runs this weekend I was seeing an almost 6#-8# increase in my Azenis bewteen runs. Damn Florida sun:D -- also got a tan
johnfelstead 01-09-2004 05:00 PM

Yep, it's been used for years. Any inert gas is preferable to compresed air.
zoomfactor 01-09-2004 05:24 PM

John - do you have any idea on how dramatic your tire temps/pressures change on a lap at the 'Ring?
dwx 01-09-2004 05:29 PM

Very popular with the Porsche track event crowd and people that are very serious about racing. I have no doubt someone has autocrossed at some point with nitrogen filled tires. There are alot of proponents of using nitrogen because it doesn't leak as fast as regular air and tires won't underinflate nearly as quickly, which reduces tire wear on passenger vehicles.

Makes it a bit harder to play around with tire pressures though. :)
johnfelstead 01-09-2004 05:38 PM

I set them hot at the end of my sighting lap, they will go up 8PSI on that i would say. They usually only change a few PSI on the first hot lap then not at all after that after the first mile.

I usually dont push too hard for the first mile of the track unless i have done a quick warm up on the roads outside the circuit to get the tyres, oil temps etc up to the correct levels.
makofoto 01-09-2004 06:07 PM

Air is already about 80% nitrogen ...

Henry Watts in his "Secrets of Solo Racing" book ... says it's not worth it ... hard to carry nitrogen around, etc. ... but the moisture content is interesting ... I wonder is tire station air filling pumps have moisture filters ... like scuba tank fillers. When you compress air ... you can get a lot of residual moisture. My air gun pump has a chamber with silicon balls where the moisture is suppose to condense. When you are finished ... you open a valve ... and you can get a plume of moisture blasting back out ...
LyveWRX 01-09-2004 07:11 PM

I think you could get a bottle from a welding supply house, and a regulator of course, a bit of investment but how much time is there btw the places at the level you drive at.

most gas stations nowadays only have little piddly compressors that you put some quarters into and out comes some dirty air... I always bleed the first bit of air out of the hose, Almost always I get some water too. In the winter not much really, more on humid cool days...

I'd bet youd be surprised at how long a 15-20# tank of N2 would last, and how cheap it is (aside from tank & regulator purchase/rental/deposit)

nick

Edit: Found on the web somewhere, home darkroom guys talking about using compressed air (from a compressor) to blow off negatives.

[quote]
"
Dave Schneider , sep 30, 2002; 09:53 a.m.
I would recommend using a cylinder of compressed nitrogen or carbon dioxide. A 15 pound cylinder (about 6 inch diameter and 24 inches tall) will last me about two years. Refill cost is about $10. The regulator and gauge was maybe $40. The advantage of this over a compressor is that you have no worry about water or oil. When air is compressed the water condenses. You need to put a filter in to eliminate the water. There may also be oil generated by the compressor which also has to be filtered.
"
[/quote]
ChrisDP 01-09-2004 08:27 PM

At a bunch of service stations I've used air pumps at, the nozzle shoots so much water out that if you hold your palm in the airstream, there will be noticable moisture on your hand in 5 seconds. Not cool, though I don't care about it for my street tires.
RacingBlue 01-10-2004 05:50 AM

We used to use a smallish CO2 bottle for a power sourse for an air gun. A little bulky but it served as an "air" source for tire fills as well. Very cheap as restaurants use it for carbonation, also used for MIG welding. The bottles are rented and exchanged.

I have also set up aluminum SCUBA dive bottles for an air source for artist air brush work. The dive shops will refill with very well filtered and very dry air (breathing quality). Nothing worse than a big clob of smutz going through the fine air brush nozzle and ruining hours of work. Any regulator overhaul dive shop has old dive regulators (1st stage) that can be tapped out for an inexpensive secondary regulator and gauge. Just attached standard air hoses and snap fittings. Beats the hell out of a noisey little crappy electric compressor running under your work area spitting out crap occasionaly.
DO NOT LEAVE BLACK DIVE TANKS THAT HAVE BEEN FILLED TO THE MAX IN THE TRUCK OF A CAR IN SUMMER. Most dive shops can show you pics of the ass end of a car blown off by the expoded overpressured tank. As I recall std refill dive bottle refill pressures are around 3,000 PSI. You will need a SCUBA certification card to get tanks refilled and of course the dive bottles must be within current inspection specs. These will drive an air gun and fill tires very well plus take you underwater.

Many shop air compressors spit not only air but airesol compressor oils and bacterial cottage cheese stuff similar to what grows in the water/oil mix of crappy diesel fuel. Of course station air compressors are rarely drained much less well filtered.

More than you wanted to know probably.
WAFlowers 01-10-2004 09:27 AM

[QUOTE][i]Originally posted by Phil Pausmer[/i]
[B]DO NOT LEAVE BLACK DIVE TANKS THAT HAVE BEEN FILLED TO THE MAX IN THE TRUCK OF A CAR IN SUMMER. Most dive shops can show you pics of the ass end of a car blown off by the expoded overpressured tank. As I recall std refill dive bottle refill pressures are around 3,000 PSI.[/B][/QUOTE]
And any competent dive shop will tell you that a properly maintained and regularly inspected (as required for refills) tank will not explode from sitting in a hot car or in the sun. There is a burst disk in the 1st stage that will let go first, releasing the pressure in a controlled manner.

In fact, an old burst disk is more likely to fail at lower pressure!

However I have seen the results of an improperly stowed tank that had the 1st stage snapped off in a sudden stop! Gives a new meaning to the term "bottle rocket". :lol:

I've been diving for 25 years, have certifications from 3 agencies and logged more hours than most instructors I know. I've discussed this with many people over many years. It seems to be an urban myth. This isn't to say that it is good to leave a filled tank in a hot vehicle though.
AlexP 01-10-2004 09:48 AM

i'm pretty sure scca solo II rules state that high pressure vessels (not sure where the distinction of "high" comes into play, but you can be sure it applies to liquid CO2 cylinders and N2 cylinders at 3000 psi) are not allowed in the pit/paddock.

just hearsay, though...
makofoto 01-10-2004 12:12 PM

You don't _necessarily_ need a Scuba certificate to have your tanks refilled. We get our Scuba and SurviAir (4,500 PSI!) tanks, that we use to fill our Olympic Style air gun reserviors, filled at scuba shops ... without having certificates. The tanks need to be "current." It seems to be up to the individual shops. You can find used but still current tanks for sale.

(obviouisly just talking about nice clean dry scuba air)
GQ 01-11-2004 07:25 PM

We (USN) use nitrogen to fill the tires on aircraft.
DetroitWRX 01-12-2004 09:09 AM

What about Helium? It�s lighter than air but I don�t know about its heating properties. Drag racers have been using Helium for years as a trick to cut down rotating mass. Helium and light weight lug nuts wow your car will fly with the rotating mass saved. :D
Rob
Thumper23 01-12-2004 10:45 AM

[QUOTE][i]Originally posted by GQ[/i]
[B] We (USN) use nitrogen to fill the tires on aircraft. [/B][/QUOTE]

Yes we do. However, that becomes a major pain when lets say, you blow a tire on landing cause of a faulty bead, for example in Albany, GA, and you get stuck there for a weekend babysitting your airplance cause the civilian contractors won't come out on a weekend and fix your flat.



:furious:



all purely hypothetical of course
GQ 01-12-2004 12:12 PM

"civilian contractors won't come out on a weekend and fix your flat."

I happen to be one of those civilian contractors
:D

What is even worse is when you have to perform a FOD walkdown of the entire runway when a tire blows.:mad:

Rob
dave bruener 01-12-2004 02:52 PM

regarding helium to fill tires, I think helium will lose pressure rather quickly because the molecules of helium are small enough to seep through the tire.
so not a good chioce for autocross or road racing, might help a bit for drag racing.
also going back to the use of nitrgen, I was told by a roundy rounder that they used nitrogen because it was the cheapest gas to buy.
LyveWRX 01-12-2004 08:22 PM

And also pefectly dry and inert. CO2 might be a little cheaper, but is acidic.
Penguinking 01-13-2004 11:49 PM

how do you get rid of the "old" air? just deflate, then inflate with the "clean air", then deflate, then inflate again...repeat how many times? cause if you do it once that'll still leave some of the old air w/ the moisture in it.
StuBeck 01-14-2004 01:56 AM

I think you just have to start with a complety deflated tire to propperly do it.
nate49509 01-14-2004 02:25 AM

[QUOTE][i]Originally posted by LyveWRX [/i]
[B]And also pefectly dry and inert. CO2 might be a little cheaper, but is acidic. [/B][/QUOTE]

CO2 is not a very stable gas anyway. Ask any paintballer.:lol:
zoomfactor 01-14-2004 08:51 AM

[QUOTE]CO2 is not a very stable gas anyway. Ask any paintballer.[/QUOTE]

Pretty funny! My sons gun at our last outing was shooting "snow".
Penguinking 01-14-2004 11:18 AM

don't they use another gas for paintball, like nitrogen or something?
chadwick101 01-14-2004 11:27 AM

[QUOTE][i]Originally posted by GQ [/i]
[B]We (USN) use nitrogen to fill the tires on aircraft. [/B][/QUOTE]


Same on our Apaches...
makofoto 01-14-2004 11:36 AM

Hey Soldier! Hope you guys are doing O.K. !?

Iran COULD be such a cool rally/off-road place ... :-(
HoRo1 01-14-2004 06:52 PM

I use CO2 in my tyres.
nate49509 01-14-2004 07:44 PM

[QUOTE][i]Originally posted by HoRo1 [/i]
[B]I use CO2 in my tyres. [/B][/QUOTE]

Your joking right?:huh:
nate49509 01-14-2004 07:50 PM

[QUOTE][i]Originally posted by Penguinking [/i]
[B]don't they use another gas for paintball, like nitrogen or something? [/B][/QUOTE]

Most of your higher end guns you have to run compressed air or nitrogen because CO2 can change into a liquid depending on the temp and freeze up the gun. One reason you wouldn't want to use it in a car. The pressure can also change radically depending on the temp. I think its also heavier than air.
Thumper23 01-14-2004 08:50 PM

[QUOTE][i]Originally posted by GQ[/i]
[B] "civilian contractors won't come out on a weekend and fix your flat."

I happen to be one of those civilian contractors
:D

What is even worse is when you have to perform a FOD walkdown of the entire runway when a tire blows.:mad:

Rob [/B][/QUOTE]


Nobody wanted the overtime that weekend
;)


So I got paid to watch TV the whole weekend. Wasn't too bad, but man was I bored.
HoRo1 01-14-2004 09:37 PM

I use CO2 because I have a "Powertank" left over from my rockcrawling phase. The Powertank holds 10lbs of liquid CO2 which enables me to adjust tyre pressures at will for a whole season (actually it will do several seasons on one charge). There is instant gas pressure - no waiting for a crappy little battery driven pump and no hauling around heavy compressors.

I check my pressures after every run and once the tyres are hot, which is after the first run, I experience no unexpected pressure changes. I have never experienced any problems whatsoever running with CO2.

The tank also holds enough gas at enough pressure to drive any air tools that I have.

I must point out that I get my tyres mounted and balanced at a local shop and they of course use air. I merely adjust pressures with CO2. I'd say that the most I've ever run with at the track is one tyre with about 75% CO2 versus 2-3% for the others.

Edit
When my CO2 charge runs out, I would consider running with nitrogen, but I would have to replace my tank with something that can withstand liquid nitrogen temperatures, which I think is about 100 degrees or more lower than CO2.

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