General recommended tyre pressures
- Thread starter pandasam
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General recommended tyre pressures
Err what the handbook says which is round 30 Psi iirc give or take a few.
Don' forget, £60 + 3 points for each incorrectly inflated tyre
Don' forget, £60 + 3 points for each incorrectly inflated tyre
doctorchris
Established member
Tyres inflated to 35 or even, God forbid, 40 psi will have a significantly reduced foot print on the road which will reduce grip and be particularly hazardous in the wet.
They will also wear abnormally quickly in the centre of tread, further reducing grip and significantly reducing the life span of the tyre.
Car manufacturers develop recommended tyre pressures after high mileages of testing and don't just think them up in their lunch breaks.
They will also wear abnormally quickly in the centre of tread, further reducing grip and significantly reducing the life span of the tyre.
Car manufacturers develop recommended tyre pressures after high mileages of testing and don't just think them up in their lunch breaks.
I think it's okay within reason to fiddle with tyre pressures. I used to do this a hell of a lot when I was tracking cars. Then I realised I could subtly alter the balance of the car a little on the road too.
I run 32 all round on my 100hp. It's supposed to be 32/30 and IIRC that's for a high load, high speed. I prefer a bit more on the rear to try and loosen the rear end up under cornering.
I would say that 40 is going too high Sam really. Don't forget that pressure will increase when hot. 35 I would say is probably about as far as you want to go.
I run 32 all round on my 100hp. It's supposed to be 32/30 and IIRC that's for a high load, high speed. I prefer a bit more on the rear to try and loosen the rear end up under cornering.
I would say that 40 is going too high Sam really. Don't forget that pressure will increase when hot. 35 I would say is probably about as far as you want to go.
40psi would be fine...... if you are carrying 6 passengers and two fully-loaded roofboxes!
I would go 34psi max - and remember to lower them again once the car has been unloaded.
Can't imagine it changes much for the 14" wheels but for our 155/80/13s it normal load 2.0Bar front, 1.8Bar rear and for high load its 2.2 / 2.0
I tend to run it slightly above normal load ,as most of the time its used there are 2 adults and a child in the car
Ride quality and handling wet n dry is 'great' with this set-up, never had issues with uneven tyre wear from inflation pressures.
I tend to run it slightly above normal load ,as most of the time its used there are 2 adults and a child in the car
Ride quality and handling wet n dry is 'great' with this set-up, never had issues with uneven tyre wear from inflation pressures.
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doctorchris
Established member
Where folk run tyres around 10% above recommended I'm sure that handling and tyre wear are unaffected. Most pressure gauges are probably 10% inaccurate if not more so the actual tyre pressures are never spot on.
Where someone considers running at 40 rather than 30 psi, 33.3% above recommended, alarm bells start to ring. Similarly, I've collected cars where tyres have been as low as 10 psi, 66.6% underinflated, due to neglect and slow punctures and the previous driver has noticed nothing wrong.
Where someone considers running at 40 rather than 30 psi, 33.3% above recommended, alarm bells start to ring. Similarly, I've collected cars where tyres have been as low as 10 psi, 66.6% underinflated, due to neglect and slow punctures and the previous driver has noticed nothing wrong.
Couple of weeks ago I had a courtesy car (panda) whilst mine was in for a bit of fettling. by the time I got it home I believed pandas had to be THE worst cars ever for cornering - until I noticed the OSF tyre looking a bit deflated.
Put my knuckle against it & it just sank straight in.
Took the car round to forecourt & checked the pressures - 20, 19, 17 & 15psi.
So every time I took a corner, I might as well have been driving on lumps of jelly!
Put my knuckle against it & it just sank straight in.
Took the car round to forecourt & checked the pressures - 20, 19, 17 & 15psi.
So every time I took a corner, I might as well have been driving on lumps of jelly!
its gonna just be a motorway cruise at about 55mph, stickin behind the lorries cause im a granny and i wanna save more fuel by slip streaming haha
its only me an a mate and a few cans of monster in the car, gonna set it at 36psi like i did last time.
its only me an a mate and a few cans of monster in the car, gonna set it at 36psi like i did last time.
I just stick mine at 30, (what they arrived at) seems to be a great compromise between grip and comfort but they do always look underinflated. I have an expensive gauge too which has been tested by a car magazine to be accurate within 3%.
I bought a Fiesta once, but I couldn't test drive it for insurance reasons, my dad test drove it. When I did get it insured I nearly crashed as the steering felt so vague and unresponsive. I checked the tyre preasures and they were all at 15psi! Needless to say I always check the preasure on any used car I am interested in now. I kept the car for two months as the rest of the car had been treated as badly as the tyres.
I bought a Fiesta once, but I couldn't test drive it for insurance reasons, my dad test drove it. When I did get it insured I nearly crashed as the steering felt so vague and unresponsive. I checked the tyre preasures and they were all at 15psi! Needless to say I always check the preasure on any used car I am interested in now. I kept the car for two months as the rest of the car had been treated as badly as the tyres.
Why does nearly everyone quote tyre pressures in psi when the handbook give them in bar It's no wonder there's confusion. By the time the bar readings are converted to psi, perhaps wrongly, God knows what pressure some people have got in their tyres
Sure, tweak the pressures if you want, but buy a bar reading tyre gauge and most importantly, read the handbook. All the information you require is there.
It's no wonder there's confusion. By the time the bar readings are converted to psi, perhaps wrongly, God knows what pressure some people have got in their tyres Sure, tweak the pressures if you want, but buy a bar reading tyre gauge and most importantly, read the handbook. All the information you require is there.
doctorchris
Established member
Tyre pressures in psi, which don't have decimals in them, are intuitively easier to remember and deal with than figures in Bar.
Oh, and psi is British!
Tyre pressures in psi, which don't have decimals in them, are intuitively easier to remember and deal with than figures in Bar.
Oh, and psi is British!
I suppose you work in Fahrenheit and £sd as well
Well don't forget your 2sec rule and then add some more!
Why?
Nope, we're not all old :devil:
doctorchris
Established member
Cheeky Geordie!I suppose you work in Fahrenheit and £sd as well
I'll have none of this new-fangled £sd system. If groats were good enough for Henry VIII, then they're good enough for us here in Sunderland.
Going way off thread, I've just discovered the financial term "fiat money", which refers to;
any money declared by a government to be legal tender.
state-issued money which is neither legally convertible to any other thing, nor fixed in value in terms of any objective standard.
money without intrinsic value.
Apparently all modern currencies are fiat money. I especially like the third definition.
The manufacturer recommends certain pressures as a result of extensive testing and to optimise the general handling, economy and safety behaviour of each particular model. I would suggest that following their advice is about right... this was covered in an earlier post, here: https://www.fiatforum.com/panda/154761-tyre-pressure.html?p=1638333
Straying too far from these can lead to unsafe handling. If you were then to have an accident, your insurance may be invalid if the car is not 'as the manufacturer intended'.
Pete
Straying too far from these can lead to unsafe handling. If you were then to have an accident, your insurance may be invalid if the car is not 'as the manufacturer intended'.
Pete
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I currently run 30psi front 32psi rear. This is mainly because i tow a trailer and have a roof box fitted in summer. When the car is not towing it does slide more readily on WET roads with these pressures. I personally think the Panda is under tyred at 155 width, it does drift very easily, even on dry roads you can induce a full slide if you get a little to enthusiastic.
Really... don't change the pressures. I recently did 2500 miles in Europe and on a long run at speed your tyres will heat up quite a lot so there is no need to inflate them higher. The handbook says what it says for a reason....
