Tyre Pressures

[ell_p]

I need all your help with this one. Picked up my Z4 drives great slight problem with steering at high speed gets a bit light and twitchy!
Thought this might be the tyre pressures all out and not to my surprise it was. Not knowing what to put in to them psi wise i put 40psi all round. the ride is alot heavier true to its line. tried reading the tyre recommendations on the sticker but doesnt really understand them as they arent in psi. i have a 3.0l si sport convertible so anyone with this car or similar please post what pressures you put in so i can get my z riding the way she should!

ps i have the 18'' multispoke wheels if that makes a difference as you can see it my lil pic <-----------------

[WLH]

I believe 40 psi might be a little high. I usually run around 34 to 36 psi and that seems to work well for me with my Goodyear F1 tires.

[sp3ctre]

I agree with WLH, I think 36 would be as high as you'd want to go.

[highstream]

got 37 back and 35 front

[Wondermike]

33 front and 36 rear for me.

[skelters]

If it's Runflats you've got then that's an added feature to the handling of the car.

The solution is to change them to other tyres and the handling instantly improves..

[BMW^Z4]

I use 2.0 front and 2.3 rear on 18", 108, pilot sport 2..

[ian in lancs]

The tyre pressures on the door sticker are in 'bars' a metric pressure unit where 1 bar is 14.5037 lb/in2. Thus 2 bars is 29 lb/in2 etc, etc.

Easy to work out with a calculator make a note to keep in the car and you'll be fine.

FWIW 40 psi (cold) is way too high for the road. IIRC a 3.0l on 18" wheels is 33F and 36R, a 2.5 on 18's is 30F and 33R both cold pressures. Warmed up they were close to 40. I used to run my 2.5 with M susp on 18's at 33F and 36R as short journeys didn't warm the tyres up much and it gave better ride and handling.