Just for fun I did change to my stock tires in rear(yes,I still have them)
And the ride height is exactly the same as before (26")
And measurement between torsion bar/center wheel is the same. So I'm still under euro height and have 26" to fender lip in rear???

Stock tire(15" 215/60-15)

Cup2 (17" 255/40-17)
/Hans
911 3.0 SC -79