Nitrogen Fill - One for the Boffins

Peter Cee · May 10, 2011

Off for a tour of Spain in June and feeling an irrational desire to fill the tyres with Nitrogen.

Remembering when I was last there a few years ago and came across a brand new Motorway in the middle of nowhere, so deserted that it felt like it hadn't been opened yet. - eventually I came accross a car on the other carriageway so that made me feel less nervous.

Inevitably all that nice smooth tarmac led to an icrease in speed till I was just the naughty side of 160mph - trouble is when I looked at the instruments the outside temperature gauge was showing 36 Dec C and I started to wonder just how hot the tyres might be getting after 15 minutes or so at that speed, so I eased down quite a bit.

Any of you Boffins out there care to give me an idea as to the effect of filling the tyres with nitrogen might be for use in those type of conditions.

Will the pressure increase due to temperature rise be sgnificantly less?

tscaptain · May 10, 2011

Now if you were a member Peter you could have a look at the 997 Tech section which has a thread on the benefits or otherwise of using N2!
There is this website link which I can copy to here
http://www.tyresave.co.uk/nitrogen.html
However, I think the key point in that piece is that it says for "ordinary road cars" which presumably doesn't include hooning across the Spanish countryside at 160mph in 36C![

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It's the water content in whatever fills your tyres that is the enemy so dry air works as well. I use N2 as I find I get less pressure rise with temp than using air from the filling station. If I knew that air had most of the moisture removed I would be happy to use that.

Lancerlot · May 10, 2011

Nitrogen is "dryer" than air, which contains moisture. This heats up and over-inflates the tyre.

Nitrogen provides a more stablised tyre pressure and does not leak out so easily. So this pressure is maintained for longer.

It will not cool overheated tyres, however. IMHO nitrogen will be beneficial for your purpose.

Regards,

Clive.

garyw · May 11, 2011

We were looking at the Spain idea, which brought a few members to comment on the new speed limits in place....

Apparently its a money earner- so eagerly applied [&:]

garyw

Peter Cee · May 12, 2011

Point taken Gary.

Always best to be cautious but the motorway from nowhere to nowhere over in Extremadura was the most deserted motorway I've ever seen. No bridges. Very few exits. Built with an EU grant according to the signs.

On both of the trips to Spain where we did around 2500 miles per trip, I can honestly say that we kept rigidly to the speed limits in all the villages and when there was traffic near busy urban areas.

Pretty soon you do find yourself on some perfect deserted roads with plenty of opportunity to stretch the cars legs.

Sometimes you come across miles and miles of twisty mountain roads which leave the cars brakes and tyres smelling like they've been on a track day.

Personally I think Spain is the best place to drive in Europe.

Go now whilst you can - one day we'll all be tracked by satellite and the party will be over

garyw · May 13, 2011

ORIGINAL: Peter Cee
Go now whilst you can - one day we'll all be tracked by satellite and the party will be over

Very true and a good point..[

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Melv · May 13, 2011

My only experience of nitrogen is in my Cup, so trackdays and sprints only.

It would appear that the tyres only need one check once the temps and pressures have stabilised and that's it, compared to 'normal' air. However downside is that the tyres cold go down to about 20-22psi so to bring pressures up I need air!!

I hope those Spanish roads are in better condition than I found them after the Olympics -the black top was fine but the foundations left a lot to be desired with catastrophic failure of some roads.......

Nick_USA · May 13, 2011

The main problem is, whilst tyres can be filled with Nitrogen when they are fitted, top-ups are usually done at a regular service station or foot pump using air; defeats the object really.

I have seen some air filters that filter out moisture and oxygen however they are typically aimed at tyres fitters and are therefore expensive.

I haven't seen a small portable Nitrogen cylinder with a tyre adapter yet, not for cars, planes yes but higher pressures involved and again cost prohibitive.

tscaptain · May 13, 2011

My local tyre place has one of these
http://www.nitrogentirefilling.com/parker-tyre-saver-tire-wand.html
and they don't mind me popping in for a quick check/top up for free (as long as I keep buying my tyres there, of course!)

Nick_USA · May 13, 2011

ORIGINAL: tscaptain

My local tyre place has one of these
http://www.nitrogentirefilling.com/parker-tyre-saver-tire-wand.html
and they don't mind me popping in for a quick check/top up for free (as long as I keep buying my tyres there, of course!)

$600 each, maybe the club should buy one and a compressor for use at the HQ or events for a small fee.

garyw · May 13, 2011

ORIGINAL: Nick_USA

ORIGINAL: tscaptain

My local tyre place has one of these
http://www.nitrogentirefilling.com/parker-tyre-saver-tire-wand.html
and they don't mind me popping in for a quick check/top up for free (as long as I keep buying my tyres there, of course!)

Click to expand...

$600 each, maybe the club should buy one and a compressor for use at the HQ or events for a small fee.

Were still saving for the Yacht after visiting Princess liners...[

]

Nick_USA · May 13, 2011

ORIGINAL: garyw

ORIGINAL: Nick_USA

ORIGINAL: tscaptain

My local tyre place has one of these
http://www.nitrogentirefilling.com/parker-tyre-saver-tire-wand.html
and they don't mind me popping in for a quick check/top up for free (as long as I keep buying my tyres there, of course!)

Click to expand...

$600 each, maybe the club should buy one and a compressor for use at the HQ or events for a small fee.

Click to expand...

Were still saving for the Yacht after visiting Princess liners...[]

[

]

In any case I am not sure 'Green with N2' valve caps goes well with my orange paint scheme !!!

Mind you these (TPMS friendly ones would be OK):

On a semi-serious note the club could get a kit, it would soon pay for itself and then make a small profit even at 10 pounds per car for a total flush and fill and say a pound per car for a top-up.

tscaptain · May 13, 2011

ORIGINAL: garyw

Were still saving for the Yacht after visiting Princess liners...[]

And then you would need to save up to afford the fuel to fill one..........[

]

I agree with Nick, a Tyresave "wand" would be most handy!

Lancerlot · May 13, 2011

Slightly bemused by some responses on this subject.

I do speak from experience as I've used N2 in my tyres exclusively for the last 4 years, in turbo, GT2 and Scuderia. There's no question in my mind nitrogen is much better. The principal point is that frequent topping up is not required as pressure is better maintained. I had my Ferrari for 2 years and only topped the tyres up once.

If air has to be used in an emergency, so what? It doesn't matter. You can soon purge and refill once it's convenient to do so.

As I understand it, the machines work by extracting N2 from the air but in this method a small amount of moisture is retained in the gas and so you can still expect a slight variation of pressure - albeit much less than air. Compressed nitrogen from cylinders on the other hand is said to be better as it contains far less moisture.

So an N2 gas cylinder, a regulator and a tyre inflater are all that would be needed. I see guys at sprints and hill climbs using bar gas (same as the pubs use) but am not sure if this is entirely suitable. However, a proper cylinder shouldn't be too expensive. You have to rent the gas bottle but the rest of the equipment is just a one off cost - a few quid. I have an account with BOC so I'll make some enquires and get back on it. [

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Regards,

Clive.

Nick_USA · May 13, 2011

ORIGINAL: Lancerlot

Slightly bemused by some responses on this subject.

I do speak from experience as I've used N02 in my tyres exclusively for the last 4 years, in turbo, GT2 and Scuderia. There's no question in my mind nitrogen is much better. The principal point is that frequent topping up is not required as pressure is better maintained. I had my Ferrari for 2 years and only topped the tyres up once.

If air has to be used in an emergency, so what? It doesn't matter. You can soon purge and refill once it's convenient to do so.

As I understand it, the machines work by extracting NO2 from the air but in this method a small amount of moisture is retained in the gas and so you can still expect a slight variation of pressure - albeit much less than air. Compressed nitrogen from cylinders on the other hand is said to be better as it contains far less moisture.

So an NO2 gas cylinder, a regulator and a tyre inflater are all that would be needed. I see guys at sprints and hill climbs using bar gas (same as the pubs use) but am not sure if this is entirely suitable. However, a proper cylinder shouldn't be too expensive. You have to rent the gas bottle but the rest of the equipment is just a one off cost - a few quid. I have an account with BOC so I'll make some enquires and get back on it. []

Regards,

Clive.

Bar (Pub) gas used to be CO2 but I now think it's a mixed gas of CO2 and N2 (70/30% mix)

Lancerlot · May 13, 2011

You're right Nick, I don't think cellar gas is suitable for our purpose. Maybe the sprint boys use it because of the convenient sized portable cylinders and self fill them from larger units.

Just done some research on legitimate nitrogen supplies.

BOC do a medium sized cylinder of oxygen-free N2 for £21.80. There's enough gas here to do dozens of vehicles. A regulator is around £40. However, rental on the gas bottle itself is £94 pa. OK I suppose if several are going to share but price would seem prohibiive for a single user.

Regards,

Clive.

Peter Cee · May 14, 2011

We use oxygen free nitrogen for pressure testing at work so with the right adapter it wouldn't be too difficult. Plus I could fill and then empty the tyres a few times to flush out the air.

I'm not really interested in the leakage rate as I check the pressures regularly

I'm only interested in the increase in pressure from cold to very hot. The question is if you fill a tyre to 30psi with air at 20 DegC how much will the pressure increase when the tyre is at say 50DegC ?

My guess would be maybe 36psi. (any racers care to comment ?)

If that tyre had been filled with nitrogen, what would the 50 DegC pressure be ?

If the difference is only small then in my opinion it's not worth the hassle.

Lancerlot · May 14, 2011

Peter,

Assuming your cylinder has some sort of a pressure reducing valve already (you don't want to be inflating tyres directly from a cylinder with 300 bar pressure) then all you need is a tyre inflater and hose. These can be bought from any local motor factors or online.

Pressure in air-inflated tyres typically increases by 6-10 psi, when hot; whereas in my experience, nitrogen filled tyres fluctuate hardly at all, but when really pushed with lots of heavy braking from high speed, may increase by 3 psi or so.

Hope this helps,

Regards,

Clive.

Peter Cee · May 14, 2011

You've convinced me.

We've got a pressure regulator so just need the air line.

okellyt · May 15, 2011

I am with Clive here

The last 2 sets of tyres I have run on N2.

Interesting point - if Quick Fit do your tyres and/or you pay for them to fill (takes 2 -3 fills top flush the air if it had air before you got o N2) then a top up is free.

As with Clive's comments, I have had to fill up far less frequently and pressure has varied significantly less under "spirited use".