Tyre Pressures

[COF139]

I'm sure that this has been asked numerous times previously, so apologies.

What is the correct tyre pressure for 235/40/18 & 285/30/18.

I normally check pressures when cold, so would be interested to understand likely variance in pressure between cold & hot tyres.

Thanks for your help.

 

[baptistsan]

36 front 44 rear iirc. Some say to drop these pressures a little as the above are really best for tackling autobahns at xxx mph. Dropping mine has resulted in a more forgiving ride, though I haven't dropped them as low as some people. Have a play with your pressures and see what suits you. Have noticed that my rears now wear evenly across the tyre with the lower pressure. In this cold weather the pressures will read lower. HTH.

 

[Terry]

When I had my 996 with those tyre sizes, I ran them at 32/40 which seemed to provide a good compromise between ride comfort and handling. Terry

 

[beershark]

I believed they were 36 & 42 which is what I run. I guess there are tolerences to personal preferences, tyres and maybe even suspension set ups ... Which leads me on to a thought Baptistan mentioned about the weather. When tracking your car, its recommened to lower the pressures as a good track session will increase the pressures above normal temperature. Makes the car very skiddy if you dont. However, my question is..... In the lower temperatures we have been experiencing recently, I think it would be wise to check & re-inflate tyres to the correct levels (when I checked mine a few days ago they were a few bar down on normal). Does that make sense?

 

[COF139]

Thanks for the responses. Much appreciated.