What/where are the correct tyre pressures?

[Poolman]

Wishing to check the tyre pressures of my relatively new Fabia, I consulted the manual. This refers me to the fuel filler flap. Crouching down and shielding my eyes against the sunlight, I can just make out the tiny print of a table, and checking the tyre size I have, discover that the correct pressure (unloaded) is 220.

220 What? In this country we use psi, why can't we be told that?

OK, I phoned a friend who told me the pressure is 30 psi (32 when loaded).

But why in the name of heaven does a manual (in English, for English users) not a) give figures in psi; not print the table in the manual? I can see the advantage of the filler flap as a backup when at the petrol station, but 220?..... Grrrrr!

[andy ellis]

Morning,

If we talking tdi/vrs then its 36psi at the front and 32psi at the rear........ Sounds a lot but the front end is VERY heavy.....

As a rough rule of thumb 220kPa is about 2.2bar......

[TeflonTom]

to convert kpa to psi you need to multiply the number by 0.14504

so 220 x 0.14505 = 31.91

[thegavsters]

Morning' date='

If we talking tdi/vrs then its 36psi at the front and 32psi at the rear........ Sounds a lot but the front end is VERY heavy.....

As a rough rule of thumb 220kPa is about 2.2bar......[/quote']

Are you sure. I was under the impression that the correct psi is 32 at the front and 31 at the back. thats how I converted the other nonsense anyway. 36 sounds incredibly high to me.

[Mr Grumpy]

Are you sure. I was under the impression that the correct psi is 32 at the front and 31 at the back. thats how I converted the other nonsense anyway. 36 sounds incredibly high to me.

I think it depends on the tyres myself.

I have Conti sp2's on mine and I've found that 35 front and 32 rear give the best performance. Bearing in mind that it gets driven 'briskly' and they are just about due for renewal at 22000 miles.

[andy ellis]

Ok from the filler cap of my TDI

.......................front...................rear

....................kPa / psi.............kPa / psi

unloaded.....230....33.............210...30

loaded.........250....36.............280...41

Know alot of people though run the fronts in the region of 34-36psi

[Poolman]

My Fabia is an Elegance, not a vrs. I do not drive it "briskly".

Would anyone like to give me the correct readings in psi?

Thanks

[TeflonTom]

i allays run me 2.0 fabia with 35psi in the front tyres,

[Reffro]

With cold tyres I set my pressures at fr 34psi, rr 32psi.

[andy ellis]

My Fabia is an Elegance' date=' not a vrs. I do not drive it "briskly".

Would anyone like to give me the correct readings in psi?

Thanks[/quote']

Probably best to run front 33 and rear at 30, but have a look at the tyres and is they seem to sagging (ie a bit like a flat) then add a few more, personally I would be thinking about a 34/32 split. I run 36/32 due to a lot of high speed work and 15" wheels. Also the fronts "look" too soft on less than 34.

[devonutopia]

I run 34 at the front, and a bit less at the back, especially as I'm usually carrying nothing back there.

On a longer journey do you think pumping up the tyres to say 38 front / 35 back would help with fuel economy (but obviously not brilliant for tyre wear?)

[Springveldt]

I always thought it was 32 front 30 rear on the VRS, that's what I've always had mine at. In saying that, my Conti's on the front got replaced at 15k and they were like F1 slicks.

[Fish]

My 1.9 tdi Elegance is fitted with 195/50 R15 tyres.

For the record, the front is 33 psi and rear 31 psi.

The conversions for BAR, PSI and KpA are:

BAR - PSI = mulitiply by 145

KpA - BAR = divide by 100

KpA - PSI = multiply by 0.145

Therefore 2.3 bar = 33 psi and 2.1 bar = 31 psi.

Lesson over!

[TeflonTom]

My 1.9 tdi Elegance is fitted with 195/50 R15 tyres.

For the record' date=' the front is 33 psi and rear 31 psi.

The conversions for BAR, PSI and KpA are:

BAR - PSI = mulitiply by 145

KpA - BAR = divide by 100

KpA - PSI = multiply by 0.145

Therefore 2.3 bar = 33 psi and 2.1 bar = 31 psi.

Lesson over![/quote']

to convert bar to psi you need to multiply by 14.7 unless what you typed was a mistake and it was supposed to be 14.5 which would give roughly the same answer anyway??

[ScoobyChris]

Used to run my Elegance at 33 front/31 rear and the car was regularly abused for 20-25k a year. Tried running them higher, but felt it drove better on the recommended settings

Chris

[Armegatron]

I run mine at 30 Rear and 32 front on a Fabia 1.4 16V comfort with 14 inch tires.

I do think bar should of been used however on the caps as its is a bit more universal than Pascals.

Anyway, just to clear up, the units used on the petrol cap are Pascals to the magnitude of 10^3 or kilo.

So 220kPa means 220000 Pascals.

A pascal is Newtons per metre (Nm-1) and bar is 10^6 dyne per cm square (dyn square cm ). A dyne is exactly 10^-5 newtons so the two are one of the same - measurements of force. (A dyne is defined as "the force required to accelerate a mass of one gram at a rate of one centimeter per second squared.")

Obviously cm and meters are also related as they are measurements of area.

Because cm are used in Bar and the dyne is 10^-5 Newtons a much smaller value can be created by just shifting the decimal point 5 places to the left. - so instead of saying "this tire pressure is 220000 Pascals", we can say "this tire pressure is 2.2Bar" Much easier IMO.

Both of the above are dependent upon the metric system (cm, m, newtons etc) However, PSI is dirty and doesnt follow the same conversion rules, hence we get different values and no easy way of converting (ie shifing a decimal point) so we have to use our noggings and multiply!

Firstly, move the decimal 5 places to the left so we go from:

220000 (pascals) to 2.2 (bar)

Then, multiply this by 14.5 to get 31.9 PSI

This is why the world needs the metric system

I feel very geeky now

PS, 220kPa is EXACTLY 2.2bar

andy ellis Morning,

If we talking tdi/vrs then its 36psi at the front and 32psi at the rear........ Sounds a lot but the front end is VERY heavy.....

As a rough rule of thumb 220kPa is about 2.2bar......

[BrOwS]

Run 34 front and 32 rear on mine.

[okeh]

Im 32/30

Might try as some have said on here

Putting a little more air in 34/32

[woodsy]

the amount of times, people have said "you have a bit of a flat" has given me the

reason to pump the fronts to 35, just to shut the buggers up!

[chris_newell41]

i did mine to 34/32 although I hadn't checked them for a while, they were 29 front and 27 back and left back was 26 :eek: although they didn't show signs of buldging on the bottom. cont' 2's!

[TommyC]

I checked my pressures the other day. Used an inflator with BAR on the gauge, so put 2.3 in the front, 2.2 in the back.

The front tyres look like they're under inflated because they bulge slightly at the bottom. I know the PD130 lump is a heavy ol' thing but surely the tyres shouldn't be doing this at manufacturers settings.

Tyres are the standard conti's (29k on the clock, newish tyres on the front fitted by previous owner).

[jec]

mmm, interesting, I thought my front tyres on Fabia VRS looked a bit flat, and I thought they should be 30psi all round. My front ones are 29 and 28,

anyway I went to top 'em up and ended up letting some out:confused: typical blonde moment!

now they are 27 and 29! :eek:

I am going to get some help and sort them out, but should I be higher than 30psi all round?

Its just a standard vrs, dunno wot tyres they are, the same ones it came with!

[Dieseline]

Just to add to the apparent confusion, I've noticed that there can be a significant difference in the pressure indicated between different pressure gauges. Garages pressure gauges aren't necessarily very accurate and from my experience neither are the pocket digital type gauges.

If you think you've correctly inflated a tyre to the recommended pressure and yet the tyre still looks a little flat then perhaps the gauge is at fault. The only way I've found to assume a reasonably accurate reading is by taking the average from several different gauges. Then for future usage I use the gauge that gave the closest to the average value. Deviation on my gauges is as high as

[SteVRs]

It amazes me how often this comes up!! The correct tyre pressures are on the inside of the filler cap.

Mine says 32F 32R. My dealer agrees and the two other Furby vRS in the family say the same. If yours says different use whatever pressures it says to use.

Edit: Buy a digital pressure meter form Halfrauds (claims to be +-0.5psi) if you don't trust your garage. Once you know how far out the local airline is you can compensate accordingly.

[r_holmes22]

It amazes me how often this comes up!! The correct tyre pressures are on the inside of the filler cap.

Mine says 32F 32R. My dealer agrees and the two other Furby vRS in the family say the same. If yours says different use whatever pressures it says to use.

Edit: Buy a digital pressure meter form Halfrauds (claims to be +-0.5psi) if you don't trust your garage. Once you know how far out the local airline is you can compensate accordingly.

It comes up because not all filler caps have the measurements in PSI, which is what a lot of us are comfortable looking for on the air pumps at petrol stations. The conversion formula is not common knowledge (I don't think it's been on the national curriculum for a while[!]), which is why people have to ask on forums like this.

I'm a little unsure about the difference between loaded and unloaded though. What are you supposed to do; add a little extra air with a battery-operated pump on your driveway while you load up your luggage then let a little out when you've unloaded at the other end!!!? Say to anybody you give a lift to "Excuse me while I stick some more air in the tyres to accommodate your significant extra weight"!!!?

:P