Tyre Pressures in winter

[SAC1]

^^^ agree.

Check and adjust if necessary the pressures from cold. So when the car hasn't been driven / no residual heat in the tyres / not parked in direct sunlight.

The onboard TPM gauge on the thumb wheel - click to the 'fill' toggle screen shows and it shows air to add / correct / reduce. This after the car has been driven for 15+ minutes and then check while stopped.

A quality accurate gauge applied to the valve, when the tyre is cold, is my preference though.

[Nuclear Nick]

Toddie, I'm with you in this one. I've combed the internet and read lots that took me back 40 odd years to physics lessons and some more about purported benefits of tyres filled with nitrogen but am no nearer an answer to the question: if a tyre should be inflated to 33psi at 20C, what pressure should it get at 3.5C? Sadly, I don't feel as though this thread has answered it ........... yet!

Just read my previous post.

[Tracky]

How many roads do you know where you can drive 80+ mph around 15 bends every 3 miles for 20minutes. That puts loads of energy and temperature into the tyres. However you will never get your tyres that hot on the road. And if you do you shouldn’t be on the road.

Come to Sussex I’ll take you out for a spin

[111rdw]

How many roads do you know where you can drive 80+ mph around 15 bends every 3 miles for 20minutes. That puts loads of energy and temperature into the tyres. However you will never get your tyres that hot on the road. And if you do you shouldn’t be on the road.

Come to Sussex I’ll take you out for a spin

[Geezer]

Here's one to ponder whilst I await the response from my OPC...just got mine back from an oil service and tyre pressures on monitor are 36 front 41 back...i gave it to them at 33/36 which I thought was right and matches other comments here...wonder why they changed them so much??

[jaffacake]

Here's one to ponder whilst I await the response from my OPC...just got mine back from an oil service and tyre pressures on monitor are 36 front 41 back...i gave it to them at 33/36 which I thought was right and matches other comments here...wonder why they changed them so much??

Sounds like they've inflated to full load pressures

[bigbaldybloke]

I thought as standard Porsche inflated the tyres with nitrogen, how many people have a nitrogen supply to top up their tyre pressures with. I compared the tpms indicated pressures with a calibrated digital gauge and they were within 0.5 psi, so now I just look at the tpms display occasionally and that’s it, they don’t seem to vary much and rarely need me to adjust them and I see minimal difference between the three with supposedly nitrogen in them and the one that had a puncture and was inflated with air at the local tyre depot.

[Tom 2000]

Toddie, I'm with you in this one. I've combed the internet and read lots that took me back 40 odd years to physics lessons and some more about purported benefits of tyres filled with nitrogen but am no nearer an answer to the question: if a tyre should be inflated to 33psi at 20C, what pressure should it get at 3.5C? Sadly, I don't feel as though this thread has answered it ........... yet!

Just read my previous post.

Indeed. Or reduce the recommended pressure for 20 degrees by 5.5% if using a manual gauge. The answer is on the Internet. I hope I am right.

[bennachie]

Air is 78.09% nitrogen after all..............................

[TheTraveller]

If you look at the valve caps of tyres filled with Nitrogen, normally they are green. But looking at different info sites, they say that Nitrogen as well as compressed air in tyres will drop in pressure as the tyres drop in temperature. All handbooks of cars say that tyre pressures should be checked when the tyre is cold, at least that is a good starting point for pressure checks. When being driven tyres will heat up, with the movement of the tread blocks, caused by friction. When stresses are exerted on them due to cornering at any speed, that too causes friction and causes them to heat up. Then the temp' of the road which will transfer the heat to them, but probably not on solid snow or ice. Therefore in winter the pressure within them will drop, and will increase less, proportionally in the colder days.