Tyre pressures

[Nattyboy62]

Hi guys

Need a bit of help please.

Have a Boxster S on a 55 plate with front tyres 235/40zr/18 and rears 265/40zr/18

Have searched everywhere to find correct tyre pressures,found a site which say fronts 33 rears 44 ? Does this sound right

Any ideas

Thanks

[thegoose]

What does the sticker in the door shut say?

[Nattyboy62]

The sticker does not apply to the 18" wheels. The car originally came with 17" wheels

[cslwannabe]

My 2007 987 S has same size tyres and factory pressures are 31 psi front and 37 psi rear.

[MadMark911]

Most owners play with the pressures a little - so my 2008 Boxster S always ran best with 31psi in the fronts and 35psi in the rears .... Same as recommended pressures in the front and a couple of psi down in the rears (which otherwise wore too much in the centre and felt too hard)!

[cslwannabe]

Only done a few thousand miles in mine so far but completely agree with MadMark911 - am also running 31 (F) and 35 (R) on my 2007 S as the rears seem to be more worn in the centre than edges.

In fact I found exactly the same with my E46 330 and current Jag XF - front pressure as recommended and rear a couple of psi lower otherwise the rears wear out in the centre. Can't say any of them ever felt any different as a result of lower the pressures.

[gsewell]

from http://www.porsche.com/all/media/pdf/Owners_Manual... page 277, I see that the 17" and 18" rims share the same pressures.

[MadMark911]

gsewell said:

from http://www.porsche.com/all/media/pdf/Owners_Manual... page 277, I see that the 17" and 18" rims share the same pressures.

Weird - I swear the pressures were different in my manual ....