I have the Weinkath C1 in 8.5x18 and 9.5x18 and currently have Vredenstein tires which I need to replace in the size 225/40-18 and 255/35-18.
But when I am looking for tires in that size (for the rear) I can´t get any N marked (porsche approved) tires.
So question is, what size should I then have (265/35-18) and what tire should I choose.
Have been looking at Continental SP2 and Michelin Pilot Sport PS2.

Tried searching but could not find a clear answer.

 

8.5 and 9.5 is odd sizing. The turbo used an 8 & 10 with 225/265. I am currently running this myself. I always like the Michelin PS2's and the new SS are quite nice. IMO a better tire than the PS2 but the SS is not an N rated tire. I find no issue running the SS's on my C2. The N rating is a tire that has been tested and then approved by Porsche. It doesn't mean that other tires should not be used but they have not been tested for one reason or another.

 

Yeah, think I will go for 225 and 265 then. The front does rub ever so slightly on the arch (screw) so I don't think I'll go up in size there.
265 should be okay for the rear, even though I have not tried.
Thank you for the reply.