Tyre temps?

[Lord_Verminaard]

Any ideas on what optimum tyre temps are for the various types of tyre in the game? Usually I just try and get the temps consistent per tyre. Thanks!

Brendan

[Pero_Grozni]

Well that is all that is to it acctually.

A few pointers though - on a slick a good 80~90 degrees Celsius should be about right for the GTC76 cars. When you start getting temperatures over 100 you know that it is too high. Make sure you check your temperatures on a straight though. If you are in a corner you anc get very strange results - more strange still if you just had a spin or a lockup.

Usually the GTC65 should run a bit lower temperatures, but I dont know for sure - I acctualy just check if the distribution is reasonable and than just drive the wheels of the thing :p

[Lord_Verminaard]

Originally Posted by Pero_Grozni

- I acctualy just check if the distribution is reasonable and than just drive the wheels of the thing :p

That's what I like to hear!

Thanks.

Brendan

[Roger]

Agree with P_G, performance seems to fall away when the temps start going over 90c. Possibly the GTC65 cars about 10deg cooler (not completely sure about this as they seem to work Ok at the higher temps).

Checking temps after a spin or some scruffy laps is not great, but sometimes I will check temps at the end of a long corner (like Parabolica) to see what is happening.

Otherwise I am finding that on the wider tyres I am getting up to 2deg temp difference inside to outside - seems to work like that. With the skinnier tyres about 1 deg difference.

[Bahger]

I was wondering about this. Do you tweak pressure/camber settings for tyre temps according to the hotter front tyre or the cooler? What kind of equivalence should there be between front and rear tyre temps? When you check tyre temps in the middle of a few practice laps, what is the significance of the fact that the pressures differ radically from their initial cold settings?

[Pero_Grozni]

Basicly you do it so that it works on the colder one. Usually if you have a huge difference it must be, that you jumped into pits after a corner or a spin or something simmilar. In that case you are working one tyre much more and it will cool down on the straight. So you should go with the lower temperature - maybe kinda average the temps by feel and see what the tendency of the setting should be.
Best of course is to have front and rears on the same temperature. Usaully that should mean that you are putting the same ammount of energy on them and that should guarentee a good stable setup. That might be way oversimplified though as there are many factors that come into that (weight distribution, tire sizes...)

Pressure difference - that is basic gas thermodynamics.
It has to do with the fact that gas expands with increased temperature. Acctually the Ideal gas state equation goes like this
p*V=mRT
p....pressure
V...Volume
m...gas mass
R....Gas constant [287.0 J/kgK for air]
T...Temperature
So what does that mean in car tires – while driving you are deforming your tire producing deformational heating and while the tire is rubbing on the road you are getting frictional heating. Now while normal driving the input of the heating energy is considerably lower due to the fact that the friction induced heating is not high due to only a small part of the surface are rubbing with the road, However as soon as you get some more slippage that heating energy raises considerably. Braking, cornering and accelerating always induce a lot of heat, but even more heat gets into the tire if you start spinning the wheels, locking the wheels, sliding...
Anyhow – the tires alway are warming up. Now at a certain level the temperature settles as the heat flow that is cooling the tire reaches the same level as the heat flow that is heating the tire. The cooling is temperature differance dependant and therefore the higher the temperature, the higher is the cooling flow.
Yes I realise I am complicating things – just want to keep everything covered and more understandable.
Anyway – the tires reach a higher temperature. The tires are filled with gas – in our case that is air. Now sonsidering the equation the right side is higher by the temperature difference and now to keep the gas state in equalibrium the left side needs to have the same resault as the right side. So there are three options – higher volume and no pressure change, higher pressure and no volume change or both volume and pressure change. That happens because the gas expands with higher temperature and if it is limmited by volume its pressure will rise or if the volume is changable without resistance the presure will stay the same, but the gas will expand. What does acctually happen in tires is that the volume does change by some ammount, but the deformation of the tire is not linear and the elasticity deformation pressure of the tire soon becomes so high, that the tire will not deform(expand) any more. So the pressure rises – again the resistance pressure of the tire must be in equalibrium with the inside air pressure. The change of pressure is that defined by the difference in temperature and the deformation characteristic of the tire. The stiffer the tire, the quicker the pressure will rise with temperature.

Hope that explains it a bit – and hopefully I didnt do a brain fart in an area or two.

[Roger]

I put nitrogen in mine to save all that worry :p

[SFDMALEX]

Originally Posted by Roger

I put nitrogen in mine to save all that worry :p

pfff methane for me. Got to put all that gas to some use..................

[Hakker]

It was found a dairy cow creates around 9 kg of volatile organic compounds (VOC) every year - more than a car - as well as large amounts of the greenhouse gas methane, possibly adding up to 20 percent of global emissions.

VOCs combine in the atmosphere with nitrogen oxides, emitted by cars, to form smog.

Cows should be more closely monitored, claims the San Joaquin Valley United Air Pollution Control District, which is behind the study.

Professor Jamie Newbold, of the Institute of Rural Sciences in Aberystwyth, told National Geographic: "In more rural communities as much as 50 percent of the methane comes from livestock.

"Actually it's belching, not farting, that's the problem. A full-grown dairy cow can belch 400 to 500 litres of methane a day."

The gases are produced by microbes in the cows' stomachs that ferment grass and food into a digestible state.

Professor Newbold went on to explain that gas creation is not only limited to cows as humans also produce methane, although without the necessary microbes it is limited to only a few millilitres.

Just to get the whole picture :p

[SFDMALEX]

Interesting........I guess I wont be starting a cow farm then................

you see my dream was a race track next to a cow farm............dreams shattered................

[Dan]

Originally Posted by Hakker

thats it, someone needs to give those cows an ultimatum..
STOP EATING GRASS OR ELSE

[Pero_Grozni]

Yes yes - I see
Cow science deffinitly is a better way of explaining things.
No wonder they float so well in the air whilst being catapulted (we need Monty Pyhton smilies badly) :p

[Roger]

Originally Posted by Hakker

"Actually it's belching, not farting, that's the problem. A full-grown dairy cow can belch 400 to 500 litres of methane a day."

And after a curry and few lagers???