Can anybody tell me what would be about the maximum spacers I could fit at the rear of a Carrera S with the std 19" wheels without making the wheel move out too much or risking the tire scrubbing on the fender?

Is 15mm ok or too much?

 

On my 2006 997, the 15mm were OK at front but just too far out at rear, so I settled for 10mm all round.

7mm is also a popular choice for front spacers.

Of course it's all subjective and personal taste!

PS - if you have the Bridgestone 050's tires (as I do until the Michelin Super Sports come out in April) they also are a lot fatter than the Michelin's and will look wider with the spacers.

 

who makes 10mm spacers.?
i have 7mm all round from RSS and they are very good quality but the dont make 10s, only 15s