Tyre Pressure

[Thaihog]

I've just bought a set of Lenso Alloys complete with 265/50/20 tyres for my 2010 Pajero.

As usual the dealers have them overinflated, currently at 50 psi. Any drivers of Fortuners or Pajeros know what the correct pressure should be?

Cheers

[MoonRiverOasis]

Tyre pressure when upsizing is determined by the load index differential - for every 1 point change in load index, the pressure varies by 1 PSI in the opposite direction.

For example, the standard tyres on my Pajero are: 265/70R16 112S - 112 being the load index ("S" being the speed rating)

Thus if I were to fit:

265/50R20 112W the pressures would remain unchanged from the factory recommendations.

265/50R20 111V I should increase the pressure by +1 PSI all-round.

There should be a placard in the driver's door jamb with recommended pressures, and you'll be able to determine the load index they refer to from the spare tyre.

[MoonRiverOasis]

Also note that if the load index of your new tyres varies from OEM by more than 1 or 2 points, you've probably just fitted inappropriate tyres for your vehicle. Thus, the pressure difference when upsizing should never really vary by much more than +/- 2 PSI..

[REDRAM]

I also recommend not using air to inflate your tires!

NITRO

[Sisaketmike]

I also recommend not using air to inflate your tires!

NITRO

I'd say Naam Pliau is better. makes it much faster.

[Spoonman]

I also recommend not using air to inflate your tires!

NITRO

Nitro is a bit volatile, hit a pothole and she will most likely explode, Nitrogen on the other has been claimed for years to be a good thing, I personally thinks its an expensive useless wank for non race track orientated vehicles.

OP, I have 20's on my Colorado (275/40/20), I run them at 40psi, I found anything over this and the ride was extremely harsh, anything under and they looked flat !!!

Edited May 13, 2010 by Spoonman

[REDRAM]

Nitro-Nized tires maintain proper pressure up to three times longer because nitrogen diffuses through tire walls more slowly than air. This gives drivers several important safety and performance advantages:

* Problems associated with under-inflation are reduced. Under-inflated

tires run hotter and wear faster due to increased rolling resistance. A

tire that is 10 percent under-inflated will lose approximately seven

percent of its service life.

* Tires maintain their strength longer. Nitrogen-filled tires show twice

the life to failure in both field and laboratory tests due to absence

of interior oxidation caused by the oxygen in compressed air.

* Tires perform better. Nitrogen can help increase tire mileage by as

much as 25 percent. Tires that are properly inflated respond better to

steering input and handle better.

* Tire pressure is more consistent. Compressed air expands at varying

rates depending on the amount of water vapor it contains; nitrogen is

"dry" and expands at a consistent, predictable rate.

[REDRAM]

Volatile?

I assume you failed science!

I also recommend not using air to inflate your tires!

NITRO

Nitro is a bit volatile, hit a pothole and she will most likely explode, Nitrogen on the other has been claimed for years to be a good thing, I personally thinks its an expensive useless wank for non race track orientated vehicles.

OP, I have 20's on my Colorado (275/40/20), I run them at 40psi, I found anything over this and the ride was extremely harsh, anything under and they looked flat !!!

[Spoonman]

Volatile?

I assume you failed science!

No not in the slightest, your talking about Nitrogen, which from where I come from is known as Nitrogen.

Nitro on the other hand is also known as Nitromethane, this my friend is highly volatile.

As for your little blurb above about the benefits to have your tyres "Nitro-Nized"........ it is a wank, if you regularly maintain the correct pressures using "Non Nitro" your tyres will last just as long as your "Nitro-Nized" ones, I must say when I was running a tyre store upselling Nitrogen to the yuppies was a good little money earner for the store.

[REDRAM]

Nitromethane! In a tire.......?

Easy to see why you are no longer in the business!

Volatile?

I assume you failed science!

No not in the slightest, your talking about Nitrogen, which from where I come from is known as Nitrogen.

Nitro on the other hand is also known as Nitromethane, this my friend is highly volatile.

As for your little blurb above about the benefits to have your tyres "Nitro-Nized"........ it is a wank, if you regularly maintain the correct pressures using "Non Nitro" your tyres will last just as long as your "Nitro-Nized" ones, I must say when I was running a tyre store upselling Nitrogen to the yuppies was a good little money earner for the store.

[Spoonman]

Sigh,Redram, you really take dumb to a new level don't you, or are you just an ignorant smart ass ??

[WarpSpeed]

Yeah as in T/A'S thread regarding quality advice here on the form this kind of retort keeps the REAL professionals from responding as they don't want to open themselves up to this type of dismissive and demeaning response and continually have to deflect or justify their credentials, so only the half wits end up posting and any really valid and quality information is not shared out of fear for being unjustly accosted for it..

To me it was quite obvious he wasn't speaking of NITRO but using a shortened terminology for nitrogen, in my mind that puts you in the position of being the pedantic "dumb, ignorant smart ass" not him..

[Spoonman]

Everyone's a professional around these parts it seems.

[Spoonman]

Please tell me than warpspeed, do you have some factual evidence that Nitrogen is advantageous in an everyday road tyre versus normal compressed air, the only thing that really shines for me is the fact it is a dry air, the potential for additional moisture that can be introduced via a poorly maintained compressor would be cause for fluctuating tyre pressures during hot conditions, what are the other advantages ??

I must ask though, how does one fill a tyre with Nitrogen, what is the method for purging air from the tyre to begin with ??

[Scully]

I keep reading about nitrogen in tyres so I will just post this link for you info. I don't know if its allowed but hey ho.

http://www.tyresave.co.uk/nitrogen.html

[VocalNeal]

Everyone's a professional around these parts it seems.

Many a true word spoken in jest. Try the bike forum there are lots of the same ilk.

As far I can see putting nitrogen in a tyre probably comes from the aircraft industry where temperature differences demand a gas which responds less to heat variations but probably more from F1/circuit racing where they use nitrogen bottles (EDIT) so they don't have to rely on circuit air or power.

Nitrogen is not new, so if it was really beneficial for road going cars they would have been doing it in from the 20's and 30' when they came up with stuff like 4-valve heads and superchargers.

Why not use Helium that would reduce the unsprung weight.

Edited May 14, 2010 by VocalNeal

[VocalNeal]

Yeah as in T/A'S thread regarding quality advice here on the form this kind of retort keeps the REAL professionals from responding as they don't want to open themselves up to this type of dismissive and demeaning response and continually have to deflect or justify their credentials, so only the half wits end up posting and any really valid and quality information is not shared out of fear for being unjustly accosted for it..

To me it was quite obvious he wasn't speaking of NITRO but using a shortened terminology for nitrogen, in my mind that puts you in the position of being the pedantic "dumb, ignorant smart ass" not him..

Warp,

Agree with your first statement but the second? NITRO an abbreviation for Nitrogen? Nitroglycerin

maybe or Nitromethane maybe but nitrogen? I am sure Dodge didn't name the NITRO vehicle after an inert gas.

They did name an engine RedRam sadly the poster emulates that engine "lots or torque"

Not usually "dismissive and demeaning" as "I don't wish to lie with dogs" as the saying goes, but I'm waiting for my second coffee.

Edited May 14, 2010 by VocalNeal

[WarpSpeed]

Please tell me than warpspeed, do you have some factual evidence that Nitrogen is advantageous in an everyday road tyre versus normal compressed air, the only thing that really shines for me is the fact it is a dry air, the potential for additional moisture that can be introduced via a poorly maintained compressor would be cause for fluctuating tyre pressures during hot conditions, what are the other advantages ??

I must ask though, how does one fill a tyre with Nitrogen, what is the method for purging air from the tyre to begin with ??

Like I said no need for me to justify my credentials or my facts provided, but short answer is yes.....How about if you discredit the information instead?? I'm confident you can't because that would require empirical experience to a high degree not just a casual Google search for example......

Having said that, being more knowledgeable and vigilant then the average Joe car owner I don't use Nitrogen in my street tires due to cost and availability but that doesn't disqualify the quality of the information that was provided by the poster in question..

[WarpSpeed]

I keep reading about nitrogen in tyres so I will just post this link for you info. I don't know if its allowed but hey ho.

http://www.tyresave.co.uk/nitrogen.html

A ton of generalizations and disclaimers on that site.. But as stated I don't recommend nor have I recommended Nitrogen for street tires, for myself I've merely contended that it's benefits are factual versus atmospheric air and even the current link confirms that...

[WarpSpeed]

Everyone's a professional around these parts it seems.

Many a true word spoken in jest. Try the bike forum there are lots of the same ilk.

As far I can see putting nitrogen in a tyre probably comes from the aircraft industry where temperature differences demand a gas which responds less to heat variations but probably more from F1/circuit racing where they use nitrogen bottles (EDIT) so they don't have to rely on circuit air or power.

Nitrogen is not new, so if it was really beneficial for road going cars they would have been doing it in from the 20's and 30' when they came up with stuff like 4-valve heads and superchargers.

Why not use Helium that would reduce the unsprung weight.

I'm sorry to say that your uncertainty and misinformation about the above highlighted information tends to disqualify you from the debate.. Been using, winning/setting track records on nitrogen filled tires for more then 20 years in racing on DOT approved tires (that's street legal tires for those novices) and it's not F1... Let's not forget that I can legitimately claim that I have never had a tire failure due to over or under inflation in all of those years while numerous others have.. Take it or leave it..

[Spoonman]

Nobody is disputing the benefits of using Nitrogen on the race track, hel_l I used to use it in the rear slicks on my drag car........

This discusssion is about the benefits of using it on the actual street.

[WarpSpeed]

Yeah as in T/A'S thread regarding quality advice here on the form this kind of retort keeps the REAL professionals from responding as they don't want to open themselves up to this type of dismissive and demeaning response and continually have to deflect or justify their credentials, so only the half wits end up posting and any really valid and quality information is not shared out of fear for being unjustly accosted for it..

To me it was quite obvious he wasn't speaking of NITRO but using a shortened terminology for nitrogen, in my mind that puts you in the position of being the pedantic "dumb, ignorant smart ass" not him..

Warp,

Agree with your first statement but the second? NITRO an abbreviation for Nitrogen? Nitroglycerin

maybe or Nitromethane maybe but nitrogen? I am sure Dodge didn't name the NITRO vehicle after an inert gas.

They did name an engine RedRam sadly the poster emulates that engine "lots or torque"

Not usually "dismissive and demeaning" as "I don't wish to lie with dogs" as the saying goes, but I'm waiting for my second coffee.

I'm aware NITRO and nitrogen are completely different but once his use of the expression was explained anything after that was being just being pedantic, demeaning and argumentative, that is fact.. Additionally, questioning the posters intellect and making such demeaning comments when it was actually his lack of understanding is just a bit hypocritical to me.. Glass houses and all that.....

[WarpSpeed]

Nobody is disputing the benefits of using Nitrogen on the race track, hel_l I used to use it in the rear slicks on my drag car........

This discusssion is about the benefits of using it on the actual street.

Spooner, so that requires a demeaning and belittling attack of the poster for taking his time to participate?? Just read past it is all, or post an opposing opinion and move on but no need to be demeaning or belittling in the response. The fact remains that his (REDRAM's) information is/was correct and required no such response regardless of whether or not it pertained to racing conditions or street conditions.. I mean in the end this always about opinions and it is up to the OP to make the final decision who's he is going to follow, I'll be the first one to object to incorrect info and try to set the record straight if I'm certain otherwise, but in the end even that is still just my opinion even if based on fact and empirical experience..

Edited May 14, 2010 by WarpSpeed

[Spoonman]

correct??

Ie still yet to see factual evidence the use of Nitrogen on the street is benefcial, someone post up some legitimate evidence and I will gladly openly apologise to Redram for calling him a dumb ignorant smart ass, which I might add was to his response to me about putting nitromethane in tyres (A practice I clearly did not say that I do), nothing to do with Him calling Nitrogen Nitro.

[WarpSpeed]

correct??

Ie still yet to see factual evidence the use of Nitrogen on the street is benefcial, someone post up some legitimate evidence and I will gladly openly apologise to Redram for calling him a dumb ignorant smart ass, which I might add was to his response to me about putting nitromethane in tyres (A practice I clearly did not say that I do), nothing to do with Him calling Nitrogen Nitro.

Yes, and as highlighted above nor did he suggest it either, which prompted his response......

Now, on the nitrogen debate there are benefits to putting it in street tires, take the advice or leave it, do thorough research of your own not just one or 2 sources as the OPINIONS vary as much there as they do here. The info is out there that's all you'll get, it is my personal opinion based on empirical experience, whether or not those benefits outweigh the costs and inconvenience of seeking it out to maintain your tires is debatable and up to the OP to decide but now he has options to consider..As stated repeatedly I personally would not use nitrogen in my street tires but then again I'm a bit more fastidious about my equipment then the average "Joe car owner" who just wants to get in, start it and drive away without ever checking a thing, in which case if one wants less trouble with follow up this would be a good alternative consideration..

Edited May 14, 2010 by WarpSpeed

[VocalNeal]

I think the reason to use it is that it costs 50 baht per tyre.

Edited May 14, 2010 by VocalNeal

[Spoonman]

So lets get back to the OP's question.

I have 20" rims and tyres, 40psi is good for me.

Lots of experts hanging round, what do they recommend considering the OEM placard listing 16" tyres is no longer valid ????

[UtopiaFlorida]

Nitro-Nized tires maintain proper pressure up to three times longer because nitrogen diffuses through tire walls more slowly than air. This gives drivers several important safety and performance advantages:

* Problems associated with under-inflation are reduced. Under-inflated

tires run hotter and wear faster due to increased rolling resistance. A

tire that is 10 percent under-inflated will lose approximately seven

percent of its service life.

* Tires maintain their strength longer. Nitrogen-filled tires show twice

the life to failure in both field and laboratory tests due to absence

of interior oxidation caused by the oxygen in compressed air.

* Tires perform better. Nitrogen can help increase tire mileage by as

much as 25 percent. Tires that are properly inflated respond better to

steering input and handle better.

* Tire pressure is more consistent. Compressed air expands at varying

rates depending on the amount of water vapor it contains; nitrogen is

"dry" and expands at a consistent, predictable rate.

I have to completely agree with the under inflation matter. I loose also a lot

of air here in Thailand and my wife and I decided to get a TPMS system from

TireMoni for our car to a) save on the tire life time and to act right away

when the pressure is going down too much - good for long distances. Helps

a lot and one less headache when driving on these crazy Thai roads

[MoonRiverOasis]

So lets get back to the OP's question.

I have 20" rims and tyres, 40psi is good for me.

Lots of experts hanging round, what do they recommend considering the OEM placard listing 16" tyres is no longer valid ????

My answer (which is based on pure facts and tire ratings) wasn't good enough?