Wheel Upgrade Tyre Pressures

[deadpheasant]

Hi,

I've just bought some new refurbed alloys and tyres for my 520i. They are original BMW Star shaped alloys that came on the E34 540 Sport. I'm replacing my 15" BBS cross spoke alloys because they are quite corroded and need refurbing themselves. Plus, I quite like the idea of having slightly bigger and slighty wider wheels.

What I wanted to know is can anyone tell me what the tyre pressures are supposed to be as my the owners manual for my 520i doesn't cover this wheel and tyre combination. My new wheels are 8Jx17 and the tyre size is 235/45/17.

If anyone with these size wheels or a 540 manual which outlines the tyre pressures who can tell me would be great.

Thanks

[filip00]

i have 225 45 17, and i pump them on 2.5bar all four.

[Anthony (M5 in Calgary)]

You need a pressure differential between front and rear. Use the M5 spec 38psi (2.6bar)front, 41 rear (2.8-2.9bar).