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But can you really "set and forget"? I am still not sure that is true. I still would have thought your pressures would drop over time like with regular air - maybe not as fast due to less H2O gas. But I agree with your experiances at the race track SK because it matchs up with the physics.

This is only my opinion !! I believe that Nitrogen inflation is worth the measely $10 or so per corner as I understand that it's more stable temperature wise and has less of a tendancy to leach out over time ( based on things I've learned from 18 years in the aircraft industry ). Allowing these attributes are accurate, it's a small price to pay for a decent gain. Really, think about how much most of us spend on our cars and now think about $10 per corner ?!?!?! C'mon......

Yes, heavy commercial aircraft use nitrogen inflation in their tyres but also, it's very necessary considering that the tyres spend a large period of time in an enviroment of -35 deg C or colder and then get dropped out and incur extreme loads and often extreme temperatures.

I guess in the end, it's $40 and can't do any harm so.......why not try the nitrogen inflation for yourself and make your own judgement based on your findings. :D My 2 cents.

Gary do you know of any race cars that use nitrogen? It would be a pain in the arse to carry compressed nitrogen to each race meet.

Whereas I always seem to find air when I need it

Many, many guys use 100% nitrogen for the reasons I have posted above. A cylinder of 100% nitrogen from BOC costs less than $30, plus cylinder rental of course. When we were karting, one medium sized aluminium cylinder would last a whole year at least. Fits in the boot easily, makes pumping up tyres simple and fast, I have a cheap gas welding gauge kit for that purpose..

Note that some classes of racing don't allow nitrogen, but who would ever know?

The real trick is getting all of the air out of the tyre before you put the nitrogen in. I have a friend with a vaccum pump (air con refills) and we use that to create a partial vacuum before we fill the tyres up with nitrogen.

:) cheers :)

....

Note that some classes of racing don't allow nitrogen, but who would ever know?

....

Are you suggesting people cheat? :D

Fair point tho, how do they go about testing it? I mean in some forms of stock class racing it would make a fair difference.

meh no real difference I reckon if you get the tyre pressures OK and warm them properly on the warm up lap.

On the other hand Gary's car is a good 3/10ths quicker than mine so who knows :D

meh no real difference I reckon if you get the tyre pressures OK and warm them properly on the warm up lap.

On the other hand Gary's car is a good 3/10ths quicker than mine so who knows :)

Duncan, I never said...........well, you know what I never said.

The advantage I have found (in the classes where it is legal) is on a cold day you can not get the tyres up to full operating temperature in half a lap warm up. That's all you really get, particualry if the guys in front of you don't want you to warm up your tyres. The reverse logic applies on a hot day, late in the race. The nitrogen doesn't increase pressure as much, so you don't have to allow as much for the pressure increase.

An example of a tyre with a best pressure of 35 psi in an 8 lap race when filled with ambient air;

Out of the pits = 27 psi

End of warm up lap = 30 psi

End of lap 1 = 33 psi

End of lap 2 = 34 psi

End of lap 3 = 34 psi

End of lap 4 = 35 psi

End of lap 5 = 35 psi

End of lap 6 = 36 psi

End of lap 7 = 37 psi

End of lap 8 = 38 psi

After cool down lap = 35 psi

Compared to a tyre with a best pressure of 35 psi in an 8 lap race when filled with 100% nitrogen;

Out of the pits = 31 psi

End of warm up lap = 33 psi

End of lap 1 = 35 psi

End of lap 2 = 35 psi

End of lap 3 = 35 psi

End of lap 4 = 35 psi

End of lap 5 = 35 psi

End of lap 6 = 36 psi

End of lap 7 = 36 psi

End of lap 8 = 36 psi

After cool down lap = 35 psi

The big winners are lap 1, lap 2, lap 7 and lap 8. Faster at the start of the race, as the tyre is at best pressure earlier because you can leave the pits at a higher pressure. Plus faster at the end of the race as the tyre is not overheating due to excessive pressure, because when it overheats it generates even more pressure.

If you want an extreme example of this, listen to the drivers comments at Bathurst about how the car comes good during the session. During the day they constantly played around with tyre pressures, 1 psi here and 1 psi there, makes all the difference. Especailly important in the last session for the sprint to the flag.

I must be a caring sharing guy to give away secrets like that............... :lol:

:) cheers :)

Edited by Sydneykid

I think there's another point to consider here. I have had some experience with aluminum alloy wheels developing corrossion on the rims and allowing air to leak out. If you fill the tyre with a more stable gas like Nitrogen you're not going to get oxide build up on your wheels, hence, you probably won't develope slow leaks on your precious track wheels while they sit around.

Gary do you know of any race cars that use nitrogen? It would be a pain in the arse to carry compressed nitrogen to each race meet.

Whereas I always seem to find air when I need it

We use it in the GT3. well we did this year. we use it to operate the on board jacks also. we just have a big cylinder full of the stuff. it's not such a pain really. it's easier than carrying a compressor!

hmmm, maybe with big enough tyres we could get the car to hover lol?

in all seriousness i don't know much about gas but i would think helium may be a bit volatile.

im getting mine done thismorning for $7.50 a tyre,plus,if i get a puncher or slow leak(need more air) i go back and get it filled for FREE.

thats at JAX tyres in blacktown.

edit,the guy who fitted my wheels told me this as my tyres are kinda close to my smic, he said Nitrogen keeps the tyres COOL(is this also true)?

Edited by RSTME
  • 3 years later...

Sorry to resurrect such an old thread but I read something recently that kind of relates to this.

The idea is that instead of using nitrogen in your tyres you use de-humidified air. It's a little strange the process to get it though...

Steps.

1. Turn your car on, have A/C as cold as possible blowing towards the floor

2. Deflate your tyres

3. Place compressor in your passenger foot well, close door as much as you can to try and keep air inside the car

4. Put air in tyres

5. Turn off your car

6. ???

7. Profit

Now, I don't know about you guys but I usually show up at most an hour before a track day, usually around the 30 min mark... I'm pretty sure if I tried this I'd miss half the day :sick:

Just food for thought though, might give it a go this weekend if I can find my tyre pressure gauge. Most likely I wont though :)

i used it speedway cars for yr's tyre is at its right preasure for the start of the race and dosent gain much extra preasure during the race .

as when just using air the preasure would be set 3 to 4 pounds lower to compansate the air heating up and the presure rising b ut at the start of the race ya preasures was wrong till the tyre heated up with the nitrogen you

knew the car would handle pretty much the same during the race

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