[Mk2] [Turbo] Sorry another Tyre Thread

[Signori]

A question for people with none standard size tyres.
Does anyone have problems with their tyres catching the arch when going over bumps or potholes?
I've just had some pirelli p zero 245/40/r17 tyres put on the rear and im having this problem. The tyres say on them that the max psi is 51, should i be running anywhere near that? Currently i have about 44psi in them, is it bad if i reduce that to around 36-38? I'm not too sure because my old tyres 225/35/r17 ran on 32psi but they were smaller.

Any advice would be great.

[Marf]

What width and offset are your rear wheels?

You may need to roll the lip on the rear arches.

[Phill P]

I run my 245/40-17's at 33 psi which is fine (29 front),Don't go near 51psi,that sounds like the max inflation preasure when you fit and seat the tyre to the rim.

As for it rubbing,rub it will,you need to hire an arch roller from ebay £60 plus £100 deposit and roll them so they don't catch

[SonicSW20]

44PSI is very high, should be ~35PSI rear, ~30PSI front, depending on what you read. Using approximations as I dont know if it varies from revision to revision or NA and Turbo.

[HighwayStar]

I believe if you search somebody here has an arch rolling kit they hire out cheaply... you must have good arches though, rust or cracked paint could be a problem. If so a bodyshop would sort it for about £120-160 ish I reckon.
As for pressures so long as you're somewhere in the mid range of the recommended operating pressures (printed on the sidewall) at 33/29 ish and maintain a r/f difference of 3-5 (depending on driving preferences) you'll be fine. It's less the size of the tyre than the weight of the vehicle that influences pressures (I think!)

R.

[SFLee]

psi is presure so it do not matter what size your type it should still stay in that region i wont go more the 36 psi .