Tyre pressures

[John_D]

The other day i had a soft looking rear so i went to the local applegreen to top it up(fancy new automatic digital pump thingy)

I checked all four tyres and the other three were bang on factory specs. I had a good look at the fronts and noticed some edge wear(inside and out) signs of under-inflation. I decided to up the fronts by 0.1bar from 1.8 to 1.9 and all i can say is wow...

Im amazed at the difference such a tiny bit more pressure has made, the car feels way more planted and solid. I guess the uniroyal rainsports are a soft tire and benefit from a little extra pressure.


Has enyone else experience of deviating from factory specs and achieving good results?

[Curran]

Just checked the conversion for 1.9 bar to PSI; and its 27.5 PSI

I go with 34 PSI in the fronts and 36 PSI in the rears.

Your pressure seems a bit soft, even if its factory spec, but have the wheels changed from factory? At your pressure, it would seem a lot different. Another bump up and it would feel even better, although might feel a bit harsh initially. Would definitely consider 32 PSI anyways.
Less inside wear, less resistance on motorways too which gives better fuel economy (even though I know thats not a major concern for anyone on these forum :P)

[318 iS Cosmos]

Just checked the conversion for 1.9 bar to PSI; and its 27.5 PSI

I go with 34 PSI in the fronts and 36 PSI in the rears.

Your pressure seems a bit soft, even if its factory spec, but have the wheels changed from factory? At your pressure, it would seem a lot different. Another bump up and it would feel even better, although might feel a bit harsh initially. Would definitely consider 32 PSI anyways.
Less inside wear, less resistance on motorways too which gives better fuel economy (even though I know thats not a major concern for anyone on these forum :P)

36 seems quite high Dave! I usually go with 30 up front and 32 rears

[FunkySeeFunkyDoo]

30 front 32 at the back too, used to use 34 at both ends for the long journey to work to help with fuel economy

I don't like those automatic compressors for some reason...much prefer the old school spinning gauge type

[Gar]

On the e39 on 18's its about right I run a 2.2 bar front and 2.5 rear which equals out to about 36psi on the rear 30 would be way to low and soft for me

Iv played around with them a good bit

[Gar]

Just a quick note on them automatic ones there a c#nt if you have a flat wheel wnd need to inflate it last time it wouldn't put air in my tyre at all I find them pretty accurate overall though as a lot of the manual ones are in shite ;sometimes if you shake them they shoot up a few extra psi

[Curran]

Just a quick note on them automatic ones there a c#nt if you have a flat wheel

Ye know there is a different button you have to press if you are trying to inflate a flat or very soft tyre....assume its down to the fact there there isnt enough pressure to get a reading, so it wont inflate.

[DoktorB]

Sticker on the inside of the drivers door. May be stuck on the B Pillar...........

I always inflate to the maximum allowable indicated on the sticker.

[Curran]

Sticker on the inside of the drivers door. May be stuck on the B Pillar...........

I always inflate to the maximum allowable indicated on the sticker.

That'd be the way I'd got with OEM wheels, and tyres supplied from the factor.

I'd always check the tyre rating first, and my current ones show max pressure to be 50 PSI, so Im well within range.

Id assume lower profile tyres are less likely to suffer from extreme cases of the image below. The side walls on my Ultrac Sessanta's are very square, opposed to say a high walled 16" tyre that would be on the Turbine alloys of an E39 (Style 33s)

[Gar]

Yep pressed it numerous times but the fu'#ker wouldn't inflate there was 0 psi in it as I had just plugged it, ended up having to go to a manual one